Then came two costly mistakes that overshadowed an otherwise solid performance -- and kept the door open a bit for Geno Smith.
Sanchez led the Jets on five scoring drives through three quarters in a 37-13 victory over the Jacksonville Jaguars on Saturday night. But, he also threw an interception in the red zone and then held onto the ball too long on third down as the first half ended, keeping the Jets (1-1) from a chance at a field goal.
"We're not willing to name a starting quarterback right now," coach Rex Ryan said. "Will we name one before the Giants game (next Saturday)? I don't know, but right now, we're not comfortable making that decision."
Blaine Gabbert, meanwhile, might have settled the Jaguars' quarterback competition -- as long as his thumb is OK.
Gabbert led the Jaguars (0-2) on two scoring drives and staked his claim to the Jaguars' starting job before leaving with a sprained thumb in the second quarter. Gabbert, competing with Chad Henne, was 13 of 16 for 165 yards and a touchdown to Allen Reisner before the injury. Jaguars coach Gus Bradley said an X-ray on Gabbert's thumb was negative.
"It's unfortunate," said Gabbert, wearing a soft black brace. "It's part of the game. We'll see tomorrow what the deal is. I just dinged it up a little bit. I just got hit on the back of it. Nothing major."
Gabbert said he banged thumbs with a defensive player, who tried to swat away the ball. He was replaced by Henne, but the Jaguars announced that Gabbert was coming out of the game regardless of the injury.
"I didn't really push it," Gabbert said. "I was coming out after that series anyway. It was more precautionary, ice it to alleviate some of the swelling."
Jacksonville's Maurice Jones-Drew ran for 9 yards and had a 20-yard catch in his first game action since suffering a foot injury last October.
"It felt great," Jones-Drew said. "Getting tackled was great."
Justin Blackmon, who opened camp on the physically unable to perform list following groin surgery this summer, had three catches for 37 yards in his preseason debut.
Smith sat out with a sprained ankle, suffered in the preseason opener last Friday at Detroit, leaving Sanchez to play the bulk of the game. Sanchez finished 13 of 23 for 169 yards for the Jets before being replaced by Matt Simms in the fourth quarter.
"I felt with Geno not playing," Sanchez said, "he would have gotten another shot."
Kahlil Bell had touchdown runs of 5 yards and 1 yard in the third quarter for the Jets, and Bilal Powell had a game-high 68 yards on seven carries. Chris Ivory, who missed most of training camp with hamstring issues, ran for 13 yards on six rushes in his first preseason action.
Both teams came in with unsettled quarterback situations, and the Jets will have an interesting week after Sanchez had some good moments and some others that likely reminded them of previous years' inconsistencies.
Smith watched the game from the sideline after being told Friday that he would sit out and rest his right ankle.
"It's doing a lot better," Smith said. "It's pretty much close to being 100 percent."
Smith was cleared by team trainers to practice but walked with a noticeable limp early in the week during training camp at SUNY Cortland, and acknowledged that the ankle was sore.
Smith, the team's second-round draft pick, was intercepted four times in Wednesday's practice, including three in 11-on-11 drills, prompting Ryan to call his performance "brutal." If he's healthy, he will likely get lots of action against the Giants -- unless the Jets decide on Sanchez as the starter to open the season.
"We play it day by day, and based on what I've been told, the competition is still open," Smith said.
The Jets got off to a fast start in this one, with Sanchez leading the team on a six-play, 59-yard drive that was capped by a 23-yard touchdown pass to Cumberland.
Gabbert got the Jaguars right back on their first offensive possession, marching Jacksonville 80 yards down the field in seven plays and hitting Reisner for a 5-yard scoring pass.
After Billy Cundiff's 30-yard field goal for the Jets, Gabbert carved up New York's starting defense again using an effective no-huddle. The 18-play drive stalled, however, at the 5 and the Jaguars settled for Josh Scobee's 23-yard field goal.
Sanchez had an impressive drive of his own on the Jets' next possession, but ruined it with a throw for Kellen Winslow from the Jaguars 3 that was intercepted in the end zone by Marcus Trufant. The sparse crowd at MetLife Stadium booed Sanchez loudly, just moments after cheering him for grounding a pass near the goal line rather than taking a risky chance and turning the ball over.
Trailing 13-10, the Jets had another chance to score just before the half as they got the ball at the Jaguars 3 after Konrad Reuland recovered a muffed punt by Tobais Palmer. On third-and-goal from the 6, Sanchez scrambled as the final 4 seconds ticked away and overthrew Clyde Gates in the end zone as time expired -- prompting more boos from the MetLife crowd.
"That won't happen again," Sanchez said. But Ryan added "that one was on me" for not managing the clock better.
Jets defensive back Mike Edwards capped the scoring when he fell on the football in the end zone for a touchdown with 2:44 left in the game after Mike Kafka couldn't handle Jason Spitz's wayward snap.
Jets LB Quinton Coples left in the second quarter. A source told ESPNNewYork.com that Coples may miss 3-4 weeks with a hairline fracture of his ankle. Ryan had no immediate details on the severity of the injury for the team's first-round pick last year. ... Jets LB Danny Lansanah, in an NFL camp for the first time since the 2009 season, had an interception midway through the third quarter to set up a touchdown drive. ... The Jaguars were penalized 10 times, resulting in a loss of 100 yards.
Information from The Associated Press was used in this report.