Two words that make Patriots followers cringe? Brady injured.

There was plenty of teeth-gnashing and hand-wringing Wednesday afternoon among Patriot Nation after those two words became reality. It happened on the second day of joint practices with the Tampa Bay Buccaneers, during an 11-on-11 play against the Bucs defense.

Brady was in a shotgun formation in his own red zone. He took the snap, then fired a pass downfield. As he did so, his left tackle, Nate Solder was being pushed backwards into him by onrushing Bucs defense end Adrian Clayborn. The massive Solder landed on top of Brady, who crumpled to the ground and rolled onto his back. He immediately clutched his left knee (the same one he injured in 2008) and remained on the ground for several moments.

Eventually, Brady got up and walked gingerly to the sideline under his own power, but with members of the team's medical staff by his side. Brady appeared to try to shake the injury off, and in fact missed just one play before returning to the field. He ran a handful more plays before leaving the practice field for good. The QB was seen going into the team's indoor practice facility adjacent to the practice fields and never returned to practice. Backups Ryan Mallett and Tim Tebow shared the reps at quarterback for New England for the remainder of practice.

The play happened at a point in practice when media cameras were prohibited from recording, but a fan in the end zone very close to the play captured the moment on his cell phone and uploaded the video to the internet. It was accessed countless times by members of the media watching practice.

Afterward, both parties directly involved – Solder and Clayborn – spoke briefly to reporters anxious to get their side of the story.

"I bull rushed the tackle and apparently he tripped on Brady and fell on him," Clayborn recalled.

Solder, meantime, claimed ignorance.

"I don't know what happened," Solder chuckled self-consciously. "I'll have to see it on film."

When pressed, Solder conceded he shouldered some blame for the incident.

We're always working to protect… you know, I screwed some things up here and there. We'll work to improve it."

Initial media reports immediately following practice indicated that Brady suffered a knee sprain, but it was unclear how long he might be out of commission.

Bucs head coach Greg Schiano also addressed the media after practice and explained that he and Patriots head coach Bill Belichick had instructed their defenders to rush hard, but to let up when they got close to the QBs to allow them to throw the ball and get good "looks" on each play.

"You always have to stay away from the quarterback," Clayborn continued, "but if you get a guy on his heels, my instinct is to keep going. And that's what I did."

"Anytime someone goes down, we worry about it," added Solder. "So, we'll see what happened. I don't know at this point. There were a few different things that happened. I'll have to see it."

The unfortunate play happened on what had been a spectacular summer day in Foxborough, and the penultimate practice of Patriots training camp's open-to-the-public sessions for this season. Not exactly the way the team wanted to conclude a productive joint session with the Buccaneers.

"Anytime anybody, especially a teammate, goes down, it's a dark cloud," running back Shane Vereen remarked. "We'll see. Nobody really knows what's going on."

Patriots president Jonathan Kraft appeared on a Boston sports radio station shortly after practice and sounded an optimistic tone about Brady's long-term prognosis.

"I'm under the impression that it's probably not that serious, but that's not a definitive answer."