WHAT SHOULD be the Eagles' deepest position helped kill them Sunday. The one thing they should do best was the one thing they did worst. And Jordan Hicks hated to see it.

"It's tough to watch," Hicks said, when asked what it's like to be unable to help the Birds stop the run, after suffering a season-ending pectoral muscle tear at Dallas, Nov. 8. "Obviously, everybody feels like they can make an impact, but I've got full confidence in our guys. I believe that they're going to get everything fixed. We've got good character guys who can play at a high level. It's just about execution."

A month ago, with rookie Hicks taking the lead, the Eagles were tied for second in the NFL, allowing an average of 3.5 yards per carry. Four games later, they rank 25th, at 4.4 yards per carry. Against Tampa Sunday, it was 6.7 yards per carry, 283 yards on 42 carries.

When Hicks went down, everyone knew the other inside linebackers would have to step up. That didn't seem like a stretch; Hicks wasn't even in the rotational plans when the season began, with the Eagles featuring DeMeco Ryans, Mychal Kendricks and Kiko Alonso. But with all three battling injuries, Hicks assumed a prominent role and was outstanding. His interception against the Cowboys stands as the most recent turnover forced by the Birds' defense, tied for the league lead in that category at the time.

It was lucky that Ryans, Kendricks and Alonso were getting healthy right then, the thinking went. Two games later, Ryans seems hobbled, playing on one good hamstring. Alonso seems to be a few beats behind everyone else on the field, having played only five games since suffering an ACL tear before the 2014 season. Kendricks, who has missed three games this season with hamstring problems, seems mostly effective as a blitzer. Against the run or in pass coverage, he is far less of a force than he was a year ago.

The inside linebackers are the key to stopping the run in a 3-4 defense. The front three occupy the blockers, the two ILBs flow to the ball. The front three weren't good Sunday, but it was the linebackers who struggled most.

Two plays were especially shocking, Doug Martin's 58- and 84-yard runs, both of which took place in the first half, as Martin set a Bucs franchise record with 177 first-half rushing yards, on a dozen carries.

On the third-and-1, 58-yard run, outside linebacker Brandon Graham and defensive end Taylor Hart were lured into the backfield before the pitch to Martin outside. Defensive lineman Ced Thornton was caught inside, couldn't get off a block. Bucs tackle Donovan Smith got to the second level untouched and put Ryans on the ground. Safety Walt Thurmond took a bad angle. Alonso and corner Byron Maxwell belatedly gave chase, but couldn't close. Eventually, cornerback Nolan Carroll chased down Martin.

On the 84-yarder, a draw, Ryans and safety Malcolm Jenkins blitzed on first-and-10 and got picked up. Alonso was bulldozed by fullback Jorvorskie Lane, Alonso unsuccessfully trying to get low and outleverage Lane, instead of shedding him. On the second level, 6-5, 231-pound wideout Mike Evans blasted Thurmond out of the way.

Again, Carroll gave chase, forcing Martin to stop and cut back, which allowed outside linebacker Connor Barwin to take him down at the Eagles' 1.

"Just a lot of gap discipline that we didn't have," said Carroll, who endured a brutal day in pass coverage, partly because the Bucs' effective run game made play action deadly.

"Guys in the wrong fit. Missed tackles. That's about it," Alonso said. He said he "had my hat on the wrong side" on the 84-yarder.

"The pitch was misdirection. The draw, it got real cluttered in there, and he found a really good hole, and he broke it," Kendricks said.

Alonso, an athletic 'backer who couldn't come close to running down Martin on the 58-yarder, said his left knee feels fine. He still does swimming pool running and ices the knee, Alonso said. He hasn't sought any medical staff treatment for it in weeks, a source close to the situation said. So presumably, Alonso isn't experiencing a lot of swelling or discomfort.

Asked whether he thinks he's the same player he was in 2013, when he was the NFL's defensive rookie of the year, Alonso said, "Yeah."

Alonso played 54 of 71 snaps Sunday, his biggest workload since he returned Nov. 8 from having his knee 'scoped following the Week 2 Dallas game. He said he isn't rusty.

Chip Kelly, when asked whether Alonso is healthy enough to play an entire game, said: "I still think we're bringing him along, in terms of him progressing. The same thing with DeMeco, too. I don't think DeMeco can play a full game right now."

Kelly noted that four of the Bucs' runs accounted for 185 of their rushing yards, meaning the rush defense wasn't consistently terrible. That's a rationale the Eagles also used after giving up 204 rushing yards at Carolina - 36- and 43-yard runs made the total look worse. As if the big runs somehow shouldn't count.

"We've got to do a better job tackling; we've got to do a better job in our fits, in terms of where we're going to be in gap defense," Kelly said Monday.

"When you give up that many rushing yards, obviously, I can't say I played very well," Alonso said.

Ryans played 41 snaps, Kendricks 56. The Eagles were penalized for having too many men on the field on a Tampa Bay third-and-4, giving the Bucs one of their 25 first downs, because Alonso stayed on when he was supposed to leave, he said.

"I didn't get the personnel (call). We were in 'dime,' I should have been off the field," he said.

Kelly was asked whether, given the way the run defense looked Sunday, sub inside linebackers Najee Goode and Emmanuel Acho might merit some playing time.

"Right now, with the short week, we're going to go with what we had (Sunday)," Kelly said, before the Eagles' only full-scale practice leading up to their Thanskgiving game at Detroit. "We're not making any lineup moves at this point in time."

On Twitter: @LesBowen

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