The Eagles open the regular season in 17 days, and coach Doug Pederson is ready to start preparing. Whether his starting offense and defense are ready after a 38-31 win over the Miami Dolphins on Thursday night at Lincoln Financial Field remains a question.

The third preseason game is usually the game in which the starters play the longest, often into the third quarter. Pederson, who limited the playing time of his starters in the first two games, inserted the reserves into the game early in the second quarter Thursday. The first quarter included two scoring drives from his offense and a forced turnover from his defense. That was enough for the coach, superseding any of the sloppiness that was also apparent on both ends. His decision was also swayed by two long practices against the Dolphins earlier this week, when the starting units took on a heavy workload.

"They've got a lot of great work over two days," Pederson said. "You think about it, we played a full football game on 48 hours on two days rest. Monday, Tuesday was pretty intense for both teams. I felt like we got some work. That was part of the reason why I was able to pull them out."

Carson Wentz finished 6 of 10 for 129 yards, two touchdowns and one interception. He connected twice with Alshon Jeffery for 35 yards and a score. Wentz and the first-team offense showed improvement from last week, but they played only 18 snaps Thursday. They played 49 snaps during the preseason, which is 18 fewer than Sam Bradford and the starting offense last season.

"We moved the ball well," Wentz said, "and for the starters, it's exciting to start getting ready for Washington [in Week 1]."

The starting defense allowed points for the first time Thursday while playing 17 snaps, and the top defensive players started coming out after 48 total snaps during the preseason. That's 34 fewer than one year ago. But safety Malcolm Jenkins' message was similar to that from Wentz; the focus is on the Redskins.

"This game we planned on playing a lot longer than we did,"  Jenkins said. "Just due to the amount of reps we got this week in practice, they just decided to cut back on those. … But I think we're ready. The production was there, guys are jelling. We're excited to start working on Washington."

The defense suffocated Miami on the opening drive of the game, when Vinny Curry burst around the edge to sack Dolphins quarterback Jay Cutler and force a fumble. It was the fourth forced turnover by the starting defense this summer.

Wentz insisted earlier this week that the offense must play better on third down, and he backed that up on his first series. Facing a third-and-8 on the 50-yard line, Wentz found Torrey Smith streaking open downfield after former Eagles cornerback Byron Maxwell blew the coverage. Smith hauled in the 50-yard touchdown pass for his first catch of the preseason. The Eagles signed Smith hoping he could provide a deep dimension to the offense, so the big play was a good sign for the season.

"With a guy like Torrey, if they're going to sit flat-footed, he's going to run right by them," Wentz said.

The defense's scorching summer stretch cooled later in the first quarter, when Cutler looked deep down the right sideline to wide receiver DeVante Parker, who was covered by prized acquisition Ronald Darby. Parker has four inches on Darby, who tried to leap to make a play on the ball. Darby  mistimed the jump, and Parker hauled in the pass and ran the ball to the 2-yard line for a 72-yard gain. Miami punched it into  the end zone on the next play for the first points against the starting defense this summer.

Those points doubled two plays later. Dolphins defensive lineman William Hayes deflected Wentz's first pass, which was intercepted and returned to the 2-yard line. It was Wentz's first interception of the preseason. Miami rushed for another score to take a 14-10 lead.

Wentz responded by putting together the most encouraging drive of the preseason. Starting on his own 7-yard line, Wentz marched the Eagles 93 yards. They were helped by a penalty, but Wentz completed 3 of 4 passes for 47 yards and a 15-yard touchdown pass to Jeffery.

The two passes to Jeffery on the drive showed the connection the Eagles badly need. Jeffery has the size, speed, and route-running skills to be the top receiver, and his presence was clear throughout the first quarter. If Wentz can get the necessary protection – that was not a given  Thursday, considering he was too often under duress and on the turf – then he has the offensive weapons for improvement this season.

It also helped that the Eagles found a consistent running attack on the drive. LeGarrette Blount, who was dreadful in the first two games, wiggled his way through Miami's defense for an impressive 16-yard gain. Wendell Smallwood, playing in his first game, had a 10-yard gain around the left side. The offense was balanced on the drive, and the Dolphins had no answer. It was the type of drive that satisfied Pederson, who pulled his offensive starters after Jeffery's score.

"You'd love to have that type of balance," Pederson said. "That's definitely a sort of blueprint of what you'd like to see in the regular season."

The defensive starters did leave as favorable a final impression. Darby, who sparkled in his debut, was flagged for  pass interference in the end zone when Cutler tried to find Kenny Stills for a 43-yard score. Cutler threw a touchdown pass on the next play. That meant there were three scores against the Eagles, although one was the result of the short field from Wentz's interception. But it was still a step back after the defense thrived in the first two weeks, although it also faced a better offense.

Twelve seconds into the second quarter, the starting units were on the sidelines. Turnovers dominated the rest of the quarter. Jaylen Watkins and Mychal Kendricks both had interceptions for the Eagles. It was Kendricks' third in three games this summer.

By the time the deep reserves entered in the second half, the game was played mainly to determine roster spots. That will be the case through most of next week's game against the New York Jets in the preseason finale. By then, the starters will already be one week into their preparations for Washington.

Since the beginning of training camp, Pederson has repeatedly alluded to the Sept. 10 opener. The entire summer mission has been to try to reach that date unscathed. The Eagles made it there without any significant injuries, and 17 days remain for Pederson to show that his players are as ready as he seems to think they are.

"I feel real comfortable with where they're at," Pederson said. "Their focus now is on a couple of weeks."