Tom Brady and Rob Gronkowski were the biggest stars on the field for the Patriots for the opening of training camp 2018 at Gillette Stadium.

And the duo very much looked the part, especially the All-Pro tight end. Gronkowski caught seemingly every ball thrown his way, including plays in the end zone beating double coverage for the scores.

One thing Gronkowski didn't do a lot of, though, was celebrate or show the type of emotion that he did throughout the three days of veteran mini-camp in early June. Unlike a year ago, when Gronkowski opened training camp with obvious energy and visible celebrations, the tight end seemed to take a workmanlike approach to his first camp practice.

Brady and Gronkowski both got notable ovations from the thousands of fans in attendance when they took the field, including chants of "Brady, Brady!" from the stands. The quarterback was far from perfect, but was also the best passer on the field by far as he begins the work toward his 19th NFL campaign.

While Brady and Gronkowski were the biggest stars on the field, the biggest and maybe most notable man was left tackle Trent Brown.

The 6-8, 380-pound trade addition from the 49ers took reps at left tackle with the rest of New England's returning starting lineup, a group that included left guard Joe Thuney, center David Andrews, right guard Shaq Mason and right tackle Marcus Cannon. Thuney didn't appear to miss a beat after missing the spring with a foot injury, while Cannon is apparently also back to full-go from the ankle issue that landed him on IR last season.

Brown, who's played mostly right tackle in his career, will be battling top pick Isaiah Wynn and others for the left tackle job opened up by Nate Solder's free agent departure to the Giants. It's worth noting that Wynn also took left tackle reps with other line groups during the practice.

For his part, Brown admitted that his acclimation to the left side in New England was "going slow."

Beyond Brady and Gronkowski's star power and Brown's first look, here are one man's blogservations from a make-shift radio booth atop the bleachers at the end of the practice field:

--The only player from the 90-man roster not seen on the field was wide receiver Malcolm Mitchell. The third-year receiver missed all of last season to injury. Reports earlier this week indicated that the Patriots have been looking for a trade partner for the former fourth-round pick and that he had undergone a "procedure" on his knee.

--Other players not taking part in the practice included Matthew Slater (PUP), Nate Ebner (ACL/PUP), Jonathan Jones (PUP), Cyrus Jones (ACL/PUP), Kenny Britt (leg/PUP) and Brandon Bolen (NFI). Those players spent a large portion of time on the lower rehab field. Bolden, Ebner and Jonathan Jones did some pretty intense conditioning running on the hill between the fields later in practice.

--Prior to practice there were massive fans on the field blowing around the end zone area, possibly to dry out some extra moisture.

--The practice took place in a variety of weather conditions. Early on it was cloudy and humid. Then it drizzled leading up to a short stint of full rain. By the end of the workout the sun was out and the temperatures soared.

--Rookies are still wearing numbers in the 50s and 60, the first group of them based on their draft order. Those numbers are now listed on the roster given out to fans, though, making the observation of practice a slight bit easier.

--The goal posts and lining of the fields has rotated since June's mini-camp. While the fields were going in more of an East-West direction in the spring, they now are in their traditional North-South direction that mirrors the game field inside of Gillette Stadium.

--Running backs coach Ivan Fears was the first player/coach on the field. Cornerback Stephon Gilmore was the first player.

--Ryan Izzo was the second player on the field. The rookie tight end carried an extra helmet and pads with him, which ended up being true for most of the rookies.

--Though the attire for the practice was just helmets and sweats, it appeared the pads were put to use by some players (mostly lineman) for certain drills.

--Former Arkansas and Wisconsin coach Bret Bielema was again on the field. He is now listed in the team's media guide as the consultant to the head coach. Bielma seems to spend his practice time working with the special teams units and defensive side of the ball.

--Prior to the start of practice, and just after his first on-field press conference of training camp, Bill Belichick did some running on the conditioning hill on the far corner of the field. Belichick ran both forwards and backwards on the hill.

--Dont'a Hightower wore a large, Don Joy brace on his right knee for the practice. The veteran linebacker appeared to be a full participant after missing all but five games last season to injury, including a torn pectoral that landed him on injured reserve.

--Cornerback Jason McCourty took reps with a secondary group of secondary players throughout the practice. The veteran trade addition did not take many, if any, meaningful reps in group or team action during the spring. He was far more active on Thursday, though the results were very much mixed.

--During one session early in practice Brady and backup Brian Hoyer worked with separate groups of receivers/defensive backs in two-on-two battles. During that same time rookie passer Etling was in the middle of the field working with Rex Burkhead and James White.

--Though he's always all over the field, Belichick does continue to seem to spend more time observing the defensive side of the ball. That makes sense given the departure of coordinator Matt Patricia and the fact that the offense has a very experienced staff led by Josh McDaniels.

--At one point while on the defensive field Belichick seemed to actually coach a water boy as to where he should be in relation to the action on the field and how to best offer up water to the players. Belichick really does coach everyone on the field and never misses even the smallest detail.

--During a ball security drill rookie running back Sony Michel had the ball punched out by linebacker Elandon Roberts. Jeremy Hill had his punched free but was able to catch it before it hit the turf. Ball security will be something to keep an eye on with all the backs, especially the rookie first-round pick.

--The special teams focus of the first day of camp was the kickoff return unit. Cordarrelle Patterson led the group of returners. Also in the mix at various points on returns were Braxton Berrios, Riley McCarron and Devin Lucien, the receiver who recently re-signed with the team.

--There was a wide variety of jerseys worn by fans in the crowd. The list included an old-school Drew Bledsoe, a throwback Packers Ha Ha Clinton-Dix, Stevan Ridley and Brady Michigan No. 10.

--Patriots owner Robert Kraft came on the practice field midway through the session and watched the remainder of the workout. He spent some time chatting with Brady behind the offense while the quarterback was not in a team drill.

--Phillip Dorsett had a pretty impressive first day of practice in a pretty wide open wide receiver group. During special teams work he got some quality time with Brady and Julian Edelman on the side field. Just after that work he caught a touchdown pass from Brady in 11-on-11 action.

--The first play of 11-on-11 work was a screen pass from Brady to the rookie Michel. There were a number of other screen passes and short throws to the running backs throughout the team action. Even dating back to the spring it looks like the running backs will be a big part of the passing attack, maybe even more so than has been the case in the recent past.

--The first defensive line to take reps in many drills included left end Trey Flowers, tackles Lawrence Guy and Danny Shelton and right end Adrian Clayborn. Malcolm Brown, Adam Butler and Vincent Valentine also took high-level reps in various drills. At end, the next reps seemed to go to Derek Rivers and Deatrich Wise Jr. at left and right end, respectively.

--After the top offensive line got its reps, the next unit at times included left tackle Matt Tobin, left guard Nate Theaker, center Luke Bowanko, right guard Jason King and right tackle Ulrick John. Legendary line coach Dante Scarnecchia moved guys all around all spring and mixed various units. That's likely to continue well into the preseason as the battles for positions, roles and rosters spots plays out in the trenches.

--Bowanko and Etling had to run a penalty lap after a botched snap in one drill. Later, Brian Hoyer vocalized great displeasure when he pulled out early leading to a fumbled snap. He immediately went to run a lap, only to see that Belichick made the entire offense run due to the mistake. The coach then called the unit in to talk to the players for a few moments before returning to practice action.

--Wise had a nice batted passed on a Hoyer throw. A few minutes later Rivers looked to be in position for a pass defense of his own, only to see Etling drop his arm angle to complete the short throw to a running back.

--Etling looked solid at times with his awareness, but at one point threw a short crossing pass to running back Ralph Webb way too hard, leading to the ball deflecting off his target's hands.

--Gronkowski had his way with the safeties most of the morning, regardless of the route. Most of the damage came in the end zone.

--Both Brian Flores (defense) and McDaniels (offense) used headsets to call in the plays for their units. Worth noting that safeties coach Steve Belichick often uses hand signals to coincide with each defensive call.

--Wynn took left tackle reps with a group that also included left guard Ted Karras, center James Ferentz, right guard Cole Croston and right tackle LaAdrian Waddle. All of the players, other than the rookie, have NFL roster/game experience.

--Edelman wore black cleats for the practice.

--Brady had a pretty exuberant celebration after a touchdown throw to Michel in one group drill.

--Director of player personnel Nick Caserio was on the field and in his usual practice role throwing as an extra passer in a number of drills.

--Brady overthrew Gronkowski in the back of the end zone in 11-on-11 action. To see the respect the tight end gets from his own defense, he was bracketed by the linebacker Hightower and safeties Patrick Chung and Harmon.

--Eric Rowe got a lot of reps at cornerback working opposite Gilmore.

--Brady hit Jacob Hollister with a number of throws in the practice. The second-year tight end had a very strong opening and is very much in the mix for depth roles at the position behind Gronkowski.

--Roberts, Hightower and Kyle Van Noy took the bulk of the early reps at linebacker in team action.

--Van Noy had one of the better defensive plays of the day when he covered Michel into the end zone, adjusted his body to spin to the throw and nearly came away with an interception of a Hoyer pass.

--Chung had a nice pass defense on a Brady throw for Burkhead.

--Gronkowski beat Damarius Travis ridiculously easily for a touchdown from Hoyer on a corner route.

--Hoyer found White, completely uncovered, during one completion late in practice.

--Punter Ryan Allen was the holder on all of Stephen Gostkowski's field goal attempts late in practice.

--While the rest of the team retreated to the hill for conditioning work at the conclusion of practice, a small group of special teams players remained on the field for drills. Edelman, Chris Hogan, McCarron and Berrios caught punts. Chung and Patterson caught kickoffs. Burkhead, Brandon King, Jordan Richards, Hollister, Harvey Langi, Nicholas Grigsby, Christian Sam, Marquis Flowers, Keion Crossen and Geneo Grissom worked on coverage drills.

--Brady did some of his usual post-practice fundamental work with equipment manager Brenden Murphy. They spent a lot of time talking about hips, with Brady seemingly showing Murphy how to rotate his hips to throw a punch, or a ball.

--Etling spent a lot of time doing extra throwing after practice and was the last player to leave the field.

--Eric Lee, Grissom, Wise and Rivers stayed out late working on pass rush techniques and hand fighting.

--Those players who met with the media after practice included Gronkowski, Hightower, Devin McCourty, Jason McCourty, White, Brown, Trey Flowers and many others.

--New England will return to the practice field Friday morning at 9:15 for another session to take place in helmets and shorts, leading up to what's likely to be the first full-pads practice on Saturday morning.