For the second straight year, the Philadelphia Eagles went to Ford Field, and came away empty-handed, losing to the Detroit Lions 24-23 on Sunday afternoon in what seemed like a very winnable game. Here are five observations that standout from the Eagles' first loss of the season:

1. Hold onto the ball, Ryan

First thing's first: Ryan Mathews can't fumble that football, end of story. Regardless of whether or not the play call was a good one by head coach Doug Pederson (it wasn't), a veteran running back like Mathews can't cough that ball up, especially with 2:34 remaining in the contest. It was a clean hit from Lions cornerback Darius Slay (he wasn't done yet) that popped the ball loose, but Mathews has to notice he isn't getting the first down and needs to tuck that ball away. If he does that, the Eagles punt the ball away and pin the Lions (who had no more timeouts at the time) deep into their own territory and let the defense take care of business.

2. Despite first career INT, Wentz still impresses

Sure, everyone can question why Carson Wentz decided to throw a 50-yard deep ball to Nelson Agholor that was picked off by Slay for his first career interception when the Eagles just needed to get the ball into field goal territory. But take that last mistake out of the equation, and Wentz still played a heck of a game given the circumstances. He received no favors in the first half from his defense, but kept his composure and led a comeback that was almost successful up until Mathews' fumble. The rookie ended the game 25 of 33 for 278 yards and two touchdowns and one INT, and has a passer rating of 103.5 through four games. No worries, there.

3. Defense comes out flat, but turns it on late

Coming out of a bye week 3-0, it was expected that the Jim Schwartz-led defense would come out of the gates firing and cause the Lions offense all kinds of problems. Instead, they looked completely out of sorts in the first half. Before halftime arrived, the defense allowed touchdown drives of 75 yards (twice) and 80 yards, with Lions quarterback Matthew Stafford making it look easy out there. The second half, though, was what was expected of this defense throughout the entire game. Through four games, they have yet to allow a touchdown in the second half, and allowed just 42 passing yards. It was a tale of two halves, but the first half performance will certainly overshadow the second.

4. Penalties proves costly

14 penalties for 111 yards. Yes, the refs missed several calls and made some questionable ones, but the lack of discipline put on display by Pederson's team is inexcusable. Of course the refs can be blamed, especially when they decided to call an illegal man down field penalty on Connor Barwin. But the truth is the Eagles did everything they could to give this game away. If the Eagles don't face 2nd and long and 3rd and long on the final drive before halftime, they potentially find the end zone for a touchdown, instead of having to settle for the field goal. If Brandon Brooks doesn't get called for a (questionable) holding penalty in the fourth quarter, a 23-yard run stands and the Eagles are once again in the red zone aiming for six instead of three. It truly is remarkable the Eagles almost won this game.

5. Where were Smallwood and Barner?

After the victory over the Steelers, it seemed like Pederson had developed a strategy to get all four running backs involved in the offense. But in yesterday's defeat, it was all Darren Sproles and Mathews. Combined, Wendell Smallwood and Kenjon Barner played TWO snaps, one each. It may have been by design, but there was no reason for these two to receive basically no playing time, especially after the success they had against Pittsburgh.