DETROIT - From early in the second quarter of the Eagles' 45-14 loss to the Detroit Lions on Thursday to late in the fourth quarter, the offense had six drives and two first downs. They moved the ball a total of 21 yards. They took only 8 minutes, 45 seconds off the clock. During that span, a 7-7 tie turned into a 38-point deficit.

For all the merited consternation about the Eagles' defense, Chip Kelly's ineffective offense should not be overlooked as a major reason why the Eagles lost three consecutive games and are as close to the first pick as first place. What was supposed to be a high-powered unit can barely sputter.

The offense has failed to score in the 20s during the losing streak, and has 18 punts and only six touchdowns. Fatigue is not an excuse for the defense, but Bill Davis' group barely has time to breathe before the Eagles punt, sending their defense back onto the field.

"We've got to help the defense," wide receiver Jordan Matthews said. "We can't continue to have three-and-outs, and now they're back on the field. Those guys are human, too. They get tired."

Since Kelly has been in Philadelphia, the Eagles are 0-14 when they fail to score 24 points. The team is not built to win in the teens. It failed to reach 24 points four times in 2013 and four times in 2014. It has happened six times in 2015 – and there are still five games remaining.

The problem appears to be a combination of scheme and personnel. The Eagles' offensive arsenal is not vast – they like to major in select plays instead of minoring in many. Quarterback Sam Bradford noted that his missed practice time would not be a hindrance because the Eagles' plays don't vary much from week to week.

That's not a problem when the players are executing, the chains are moving, and the Eagles' tempo keeps opponents on their heels. But when that fails to happen, the offense becomes predictable instead of exhausting to defenses. And it's the Eagles' defense that becomes exhausted instead.

That's the talent part of the problem. Three months into the season, the same offensive woes from September are present. There's a large enough sample size to know that the offensive line struggles with protection and the wide receivers have a difficult time making plays downfield.

The Eagles struggled with injuries on offense – they played without quarterback Sam Bradford and tight end Zach Ertz on Thursday, and left tackle Jason Peters missed most of the game with an ankle injury – but the personnel problems go back to the offseason.

The Eagles released Pro Bowl guard Evan Mathis without adding any linemen, and now Matt Tobin and Allen Barbre are the starting guards and Dennis Kelly is the top reserve when Peters is out of the lineup. They did not value Jeremy Maclin in free agency as much as the Kansas City Chiefs, and first-round pick Nelson Agholor has been slow to develop while veteran Miles Austin is revealing why he's on his third team in three seasons. The Eagles' outside receivers combined for only seven catches on Thursday.

When Kelly was asked about the three-and-outs Thursday, he lamented the Eagles' pass blocking. Quarterback Mark Sanchez was sacked six times and hit nine times. The Eagles especially had a difficult time blocking Lions defensive end Ziggy Ansah, who had 3.5 sacks, one forced fumble, and one fumble recovery.

"They were only rushing four, and they generated a lot of pressure on Mark at times," Kelly said. "We didn't do a good from a protection standpoint."

But the Eagles' offense needs a consistent rushing game to be successful, and they finished with only 68 rushing yards and 2.7 yards per rush on Thursday. DeMarco Murray, who led the NFL in rushing with Dallas last season, finished with 30 yards. He has reached 100 rushing yards just one game this season. By this point last year, he had 10.

"I think it's everyone," Murray said. "It's not one guy, it's not one position, it's just the entire team. We've got to continue to get better. I think at the end of the day you've got to look yourself in the mirror, and come to work very day and work as hard as you can, and just control what you can control, and I think that's every guy in this locker room and every coach."

The Eagles' running game was better with Ryan Mathews in the lineup, so he'll help whenever he returns from a concussion. Bradford appears on the verge of taking his spot back, which could help the passing game. So could Ertz's return. Peters and center Jason Kelce have extended time to recover after entering Thursday's game with injuries.

But that will merely bring the Eagles back to where they were earlier in the season, when they were still inconsistent. They've scored in the thirties just twice this season. They scored in the thirties eight times in 2013 and nine times in 2014.

Maclin, Mathis, and LeSean McCoy are not on their way back. The Eagles need to find ways to score with the players they have. They were a top five scoring offense the last two seasons, and they're No. 20 this season.

It's easy to blame the defense after allowing 90 points in two weeks, but don't forget an offense that only has 31 points during that span.

Extra points

The Eagles signed defensive back Jaylen Watkins off the Buffalo Bills practice squad and placed cornerback Nolan Carroll on injured reserve. Watkins was the Eagles' 2014 fourth-round pick. They released him after the preseason. His return means the entire 2014 draft class is on the 53-man roster for the first time because safety Ed Reynolds was promoted from the practice squad last week.

Carroll suffered a broken ankle in Thursday's loss. He is a free agent at the end of the season. Eric Rowe is expected to start in his place.