The Jets (3-10) fell to the Dolphins (6-7), 34-10, at MetLife Stadium on Sunday. Here are three takeaways from the game.

UDFA QB Steps Into the Fire
Rookie QB Brady Cook was signed to the active roster ahead of Week 14, and with QB Justin Fields out with a knee injury, the Missouri product was named the backup to Tyrod Taylor. Taylor sustained a groin injury during the first quarter of Sunday's loss, and Cook took the field trailing by 21-0.

"Supreme confidence," RB Breece Hall said of the rookie's demeanor. "He takes every rep in practice like a pro. Once I heard how he came in and commanded the huddle, I was like, 'Alright, he isn't nervous. He'll be alright.' We could have been better for him tonight. … As an offense, I think we could have easily made a few more plays for him and Tyrod as well."

Cook finished the game 14-of-30 for 163 yards with 2 INTs. He connected with 6 pass catchers in the loss.

"To have this tape, this experience to watch, to build on, to learn from, however many reps I got today -- that's going to be huge for me," he said.

Isaiah Williams Provides Spark with Punt Return TD
Isaiah Williams made two costly mistakes in the return game when the Jets faced the Dolphins in Week 4, but it was a different story against the same opponent on Sunday.

Williams returned a punt 78 yards for a score late in the first quarter, marking the Green & White's lone touchdown of the day. It was his second return TD of the season.

"He's hardnosed, hardworking," HC Aaron Glenn said. "He works his craft day in and day out. He understands the nature of being a returner and he understands how to set his blocks up."

Special teams, led by first-year coordinator Chris Banjo, continues to establish itself as one of the top units in the league this season.

"The belief of everybody that's on that team -- you have to believe that the returner is going to score, and our guys sustain their blocks, they work their [expletive] off to make sure that they give him a lane to beat or run," Glenn said. "And Isaiah does a really good job with his vision to be able to see it and make the necessary cuts to go score."

Slow Defensive Start Contributes to First-Quarter Deficit
In the first quarter of Sunday's loss, the Jets fell into an early deficit.

"They scripted a good first 15 [minutes]," edge Jermaine Johnson said.

The Dolphins, who won the coin toss and elected to receive, made a statement right away. Miami QB Tua Tagovailoa led a 69-yard, 4-play drive that took 2:14 and included 2 explosive runs for 21 and 39 yards, respectively. Tagovailoa found WR Jaylen Waddle in the end zone for a 3-yard TD to take the early lead.

"We knew they were going to come out fast," LB Quincy Williams said. "The biggest thing was us coming out fast too. We didn't do that the first series. There was a lot of movement, a lot of smoke and mirrors to get us off our spot. And we didn't show up early."

The Dolphins found the end zone on the next two possessions to push the score to 21-0. The Jets defense tightened up through the middle of the game, allowing only a field goal until the fourth quarter. The slow start, however, proved costly. Miami recorded 199 total net yards and picked up 11 first downs in the first stanza, maintaining possession for 11:05 compared to the Jets' 3:55.

"As a defense, we did finish better," LB Jamien Sherwood said. "Obviously, it didn't show on the scoreboard, but we felt it. It's just minute details that we have to fix to prevent them from going up 21 points on us."