Brady Cook confronted a daunting challenge when he entered Sunday's game against Miami late in the first quarter, with the field already tilted against the home team and the Jets trailing by 21-0.

The undrafted free agent (UDFA) out of Missouri, where he was a three-year starter against top competition in the SEC, entered the game at the 2:19 mark after Miami scored 3 TDs. Starter Tyrod Taylor was forced to leave the game with a groin injury after two offensive series.

"Definitely a challenge, but a great challenge, one that comes with the job of being the backup quarterback," Cook said after the Dolphins' 34-10 victory at MetLife Stadium on a gray and chilly Sunday. "I felt ready to play today, and obviously didn't do enough to get a win."

Cook was elevated to the active roster from the practice squad when Justin Fields, Taylor's backup the last two games, was ruled out with a knee injury. With few reps in practice and facing his baptism of fire in the NFL, Cook acknowledged some early jitters, a fumbled snap and putting a bit too much mustard on passes while also dealing with a couple of dropped passes.

"I think it was on my part, maybe just a lack of trust on the timing, not quite sure where everyone's going to be exactly when they're supposed to be there," said Cook, who finished the game hitting on 14-of-30 passes for 163 yards and a pair of INT. "So I think you might actually put a little bit extra juice on it, and it might appear that way."

With the Jets (3-10) forced to chase the game early, Isaiah Williams latched onto a punt and returned it 73 yards for a TD with 42 seconds left in the first quarter. For the remainder of the first half, the Jets' defense tightened, holding Miami (6-7) to a field goal. Before the end of the half, Cook and the offense found a bit of rhythm after he connected with John Metchie III for 10 yards and then got into the red zone when Williams was interfered with by Minkah Fitzpatrick on a long pass along the visitors' sideline. The play was good for 39 yards to Miami's 16.

Three plays later, with 37 seconds left in the half, Cook's pass intended for Metchie in the end zone came up short and was intercepted by Rasul Douglas.

"Forcing the ball in the end zone, trying to make plays at the end of the half," Cook said. "Throw the ball away, find your check down."

On the Jets' third possession of the second half, which spanned the third and fourth quarters, a fake punt that RB Isaiah Davis turned into a 20-yard gain kept the drive alive. In rapid fashion, Cook completed a 15-yard toss to rookie TD Mason Taylor (5 catches, 51 yards), a 17-yard pass to Andrew Beck to Miami's 24 and another one to Taylor for 13 yards. After Breece Hall ran 6 yards to the Dolphins' 7, Cook's pass to an open Metchie slid off his hands and could not be corralled.

"I think we just ... personally, I got to be better," Metchie said. "We got to execute. We got to take advantage of all the looks and opportunities that we get out there, regardless of who's out there, regardless of who's throwing the ball."

Cook was harried throughout the game by Miami's defensive front, which sacked him 6 times and Miami's second interception with 1:19 left to play sealed the result.

"It's always tough, I mean that's the nature of being a backup quarterback," HC Aaron Glenn said. "But that's really any position, you're not going to get all the reps that you want to get during the week, but mentally you have to have yourself ready to play. And for the most part, I think he was. I thought Miami did a really good job of pressuring, they brought the house a couple of times on him, but we got to do a better job."

For Cook, being thrown into the game with limited preparation was a challenge, not an excuse.

"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," Cook said. "I look forward to seeing the tape, building off of it.

"However the reps shake out this week, next week, I'm going to be ready to play, whether the starter, whether the backup, whether the third string, it doesn't matter. I'm going to be ready to play, ready to win the Jets a football game. I think it's going to depend on how the tape looks. You know, I'm going get to watch it here shortly, and I'm going to adjust, go back to work tomorrow, and we'll get it right."