"When you drop back from 9-on-7 and see your starting flanker getting carried away in a gold cart, that's not a good way to start your day," said Gruden. "I think he's going to be ok, but I don't want to speculate because I don't have all of the facts."
The injury occurred when McCardell and Bucs cornerback Brian Kelly got tangled in the end zone while fighting for position on a pass.
While Gruden doesn't think the knee sprain is serious, the team will X-ray it during lunch and will update the media after the afternoon practice.
"It doesn't look like it's serious," said Gruden. " But it looks like he'll be out a day or two. We can update you further after lunch."
McCardell's injury gave younger Bucs receivers like Milton Wynn, Marquise Walker and Darryl Daniel more playing time during the morning practice.
"It's the worst (nightmare)," said Gruden. "You hate to see any player go down injured and a Keenan (McCardell) is obviously new here. He was just starting to find his rhythm as a receiver in this system. Meanwhile, this gives us a chance to see where we are with our other young receivers that we need to step up. This will give them a chance to do that."
Tampa Bay was missing some other players during the morning practice. Bucs running backs Michael Pittman and Travis Stephens dressed and warmed up with the team, but they were held out of the majority of team drills.
"Michael Pittman returned in a limited fashion to practice today as did Travis Stephens," said Gruden. "But both those guys are not yet 100 percent. We'll monitor them and see how they feel this afternoon."
Pittman has suffered a "setback" with his ankle sprain. He has swelling in it and on Monday morning, Gruden indicated that the injury could be something that hangs around longer than they'd like it to.
"Mike (Pittman) has some swelling in his ankle and he's not 100 percent," said Gruden. I don't know what percent he is. If you wait until the swelling is completely gone, he might miss the whole training camp. He's very close and if we played a game today or this week, he'd go. But he's not ready (to practice) right now, so we're going to keep him in the house until he's ready."
Bucs defensive tackle Warren Sapp sported a leg brace during the morning practice and didn't participate. He is expected to return to practice on Tuesday.
"Warren Sapp was held out today," said Gruden. "He has a little swelling on his knee, but it looks like he'll be home tomorrow."
Tampa Bay defensive end Marcus Jones still was resting his shoulder -- the same shoulder he had offseason surgery on, which caused him to miss two of the Bucs' three mini-camp workout sessions. Jones also is resting a sore groin injury.
"Marcus Jones is making some strides, but he too has some lingering soreness in his shoulder and his groin," said Gruden. "He (Marcus Jones) is a really important guy on this football team. He's frustrated because he wants to come out here and show us all what he can do. But before we give him the green light, we're going to make sure he's alright."
Bucs WR E.G. Green (calf) and defensive end John Stamper (hamstring) didn't participate during the morning practice. Tampa Bay offensive guard Marcus Jenkins was also held out of practice.
GRUDEN PLACES OFFENSE IN TOUGH SITUATION
Gruden added a wrinkle to Tampa Bay's offensive practice routine on Monday morning when he had the offense start some drives from its own one-year line.
The offense didn't fare well at the beginning of this drill. On the first play from scrimmage, one of Tampa Bay's offensive lineman jumped offsides due to quarterback Brad Johnson's hard count. On the next play, Bucs fullback Mike Alstott found a hole in the defense, but fumbled the football and watched the defensive recover. Needless to say, Gruden wasn't impressed.
"The first series was tragic," said Gruden. "We used the hard count and jumped offsides and then we fumbled the football, so that's the end of the day for that group. I thought the second group pounded away pretty good. You can't have error on your own one-yard line. We practiced that situation along with the two-minute drill today for the first time. You have to see on film what you're coaching. Hard count usage, ball security -- we didn't see that today and I'm very disappointed."
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