INDIANAPOLIS (AP) The Indianapolis Colts spent Wednesday adapting to the new reality that leading tackler D'Qwell Jackson will miss the last four games of the regular season.
One day after the league suspended Jackson for violating the league's performance-enhancing substance policy, inside linebackers Edwin Jackson and Antonio Morrison were getting acclimated to being the defense's new signal-callers. Others tried to fill the void of one of the Colts' steadiest locker room leaders.
''It's an obvious letdown,'' tight end Dwayne Allen said. ''We want those guys on the field, but we also understand mistakes happen.''
Neither the league nor the Colts have said what substance Jackson used.
Jackson won't be permitted back at the team complex until Jan. 2, when the Colts will either be cleaning out their lockers or preparing for a playoff game.
The timing couldn't be worse.
After losing their first two games, the Colts (6-6) have been fighting to get back into playoff position . Now, with three wins in four games, Indy has moved into a three-way tie atop the AFC South with Houston and Tennessee, and seemed to be building momentum for the key stretch run.
Suddenly, the offense appeared to be in sync, the defense was holding up better and everything seemed to be clicking.
Then less than 24 hours after finishing a 41-10 thrashing of the New York Jets , NFL officials made the announcement.
The 33-year-old inside linebacker made his only Pro Bowl two years ago and was having another solid season with 81 tackles - 21 more than anyone else on the roster. He also had one sack and recovered two fumbles.
But the more problematic issue is that Jackson was the most experienced inside linebacker on the team and, until Monday night, almost exclusively called the defenses.
Edwin Jackson, who had never played in an NFL game until this season, got his first real taste of signal calling in short bursts against the Jets.
''That was very important because that was my first time actually getting the calls and relaying it to the defense,'' Edwin Jackson said. ''You don't want these things to happen, but it happens.''
The switch may have been coming regardless of the failed drug test.
D'Qwell Jackson left Monday night's game in the fourth quarter with a concussion and had already entered the league's mandated concussion protocol. Because it usually takes players the better part of a week to clear all the steps, Jackson's status on a short week already could have been in jeopardy for Sunday's crucial game with Houston.
Losing him for four games, though, will be a bigger blow for a team that hasn't been above .500 all season. Indy still must visit AFC West leader Oakland and playoff contender Minnesota before closing out the season at home against struggling Jacksonville.
Coach Chuck Pagano knows it will require more than just good play from Edwin Jackson, an undrafted player who spent last December on Indy's practice squad. There's Morrison, a fourth-round pick out of Florida; Josh McNary, a third-year player from Army who has done most of his work on special teams; and Luke Rhodes, a rookie from William & Mary who was promoted from the practice squad to the active roster Wednesday.
''Antonio's tough, he's smart, he knows the defense inside, out. He's a downhill, sideline-to-sideline guy. He'll be fine,'' Pagano said. ''He's been told from Day 1 to prepare as a starter for this moment and he's done that. So that will give him a chance to play well.''
The Colts certainly need Morrison - and everyone else - to play well until D'Qwell Jackson returns.
''It's the National Football League and you're going to have adversity and you're going to have obstacles,'' Pagano said. ''We've been without our quarterback before. Do you want to be? No. We've been without (Robert Mathis) before. So it's next man up.''
NOTES: Right guard Denzelle Good was diagnosed with a concussion during the Jets game and nose tackle Zach Kerr and outside linebacker Curt Maggitt both complained of concussion-like symptoms after the game. All three are also in the league's protocol. ... Mathis is listed as day to day with a biceps injury, and safety Clayton Geathers is considered week to week with a neck injury. ... Offensive lineman Joe Reitz, an Indianapolis native, was selected as the team's Walter Payton Man of the Year Award winner.
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