LeSean McCoy has no excuses for his poor start.

While coach Chip Kelly insists injuries on the offensive line are the reason why the Philadelphia Eagles have struggled to run the ball effectively, the All-Pro running back points to himself.

"I'm just not getting it done," McCoy said. "I don't know what to tell you."

McCoy led the NFL with a franchise-record 1,607 yards rushing last year, helping the Eagles win the NFC East title. He set 2,000 yards as his goal this season. At this rate, 1,000 yards will be tough. McCoy had 192 yards and averaged just 2.7 yards per carry in the first month.

"I'm still confident. I know what I can do," McCoy said. "It doesn't really bother me that much. We're winning games. We're 3-1. At times it can be frustrating, but at the end of the day I know who I am."

The Eagles had stability and consistency on their offensive line in 2013. The same five players started all 17 games, including a playoff game. Left tackle Jason Peters and left guard Evan Mathis were All-Pro picks and center Jason Kelce had an excellent season.

Mathis injured his knee in Week 1 and won't return before November. Kelce had sports hernia surgery last week and is out indefinitely. Right tackle Lane Johnson, the No. 4 pick last year, missed the first four games because of a suspension for violating the NFL's substance abuse policy. His backup, Allen Barbre, sustained a season-ending ankle injury in the opener.

When the Eagles host the St. Louis Rams (1-2) on Sunday, they'll be starting their fourth line combination in five games. Johnson's return means Todd Herremans moves back to right guard, giving the Eagles three-fifths of their original starters.

"I got my boy Lane back," McCoy said. "Hopefully it works out. That definitely helps. I got used to those guys and I know how well they block. Last year, I had the whole entire line healthy for 16 games. They did tremendous. Hopefully everything will work out. I don't know if I can tell you exactly what's going on. The truth of the matter is, we're not getting it done."

Kelly showed no confidence in the makeshift line when he called pass plays on two cracks from the 1 late in the fourth quarter in a 26-21 loss at San Francisco. Nick Foles threw consecutive incompletions and the 49ers held.

McCoy finished with 17 yards on 10 carries last week. He ran for 22 yards on 19 carries in a 37-34 win over Washington in Week 3.

"I think LeSean is kind of playing the way he played last year," Kelly said. "Specifically, if you look at last week's tape, there wasn't a lot there, and it was tough sledding for anybody that was carrying the football last Sunday.

"We're not blocking very well at wide receiver, at offensive line, at tight end, anywhere. You look at our production in the run game and it's not where it should be," Kelly said. "So there's not one specific area. I think everybody from a blocking standpoint needs to improve."

McCoy was one of the top three picks, if not No. 1 overall, in many fantasy football drafts, so plenty of fans are waiting for him to break out of his slump. He has only one score while backup Darren Sproles has two rushing touchdowns.

"It's definitely frustrating," McCoy said. "You know what type of player you are and you want to put the numbers up. If teams do come in to try and stop you and they're successful with it, that's another frustrating thing."

Defenses play to stop the run against the Eagles, putting an extra defender in the box. That allowed Foles to take advantage with some play-action fakes. He led the NFL in yards passing through the first three weeks before a subpar performance against San Francisco.

"I just think we need to execute better," offensive coordinator Pat Shurmur said.

NOTES: LB Mychal Kendricks didn't practice again Thursday because of a calf injury. He's expected to miss his third straight game Sunday. Emmanuel Acho and Casey Matthews continue to fill in for him. "They are giving you what they have got and they are both very intelligent football players who can key and diagnose very well," Kelly said. ... CB Brandon Boykin returned to practice. He has a hamstring injury.


AP NFL websites: www.pro32.ap.org and www.twitter.com/AP_NFL


Follow Rob Maaddi on Twitter: https://twitter.com/AP_RobMaaddi