With Tebow inactive as he heals from two broken ribs, coach Rex Ryan pulled Sanchez for McElroy as the crowd at MetLife Stadium cheered wildly late in the third quarter.
McElroy then led the Jets (5-7) to their only points of the day with an impressive 10-play drive, rolling out to his right on a bootleg and tossing a 1-yard pass to a wide-open Jeff Cumberland in the back of the end zone 5 seconds into the fourth quarter.
Fans chanted "Mc-El-Roy!" throughout the first three quarters as Sanchez went 10 of 27 for 91 yards and three interceptions, including two by former Jets safety Kerry Rhodes. As McElroy got the offense moving, Sanchez stood on the sideline along with Tebow next to offensive coordinator Tony Sparano the rest of the way.
McElroy, reading the plays off his left wristband after getting few snaps in practice all week, was cheered with each completion, including a 13-yard toss on third down to Jeremy Kerley with 3 minutes left that sealed the victory. McElroy finished 5 of 7 for 29 yards.
Sanchez left with 4:48 left in the third quarter and the Jets trailing 3-0 after having a pass batted down by Ronald Talley. Sanchez was met on the sideline by Ryan, who said something to his quarterback as McElroy began to warm up.
It should make for an interesting week around Jets camp. If Tebow is healthy enough to play, he could be in line to start next week at Jacksonville against his hometown Jaguars.
If not, Ryan will have to take a hard look at McElroy, a seventh-round pick out of Alabama last year who missed all last season with a thumb injury.
While the Jets' quarterback situation is unclear for the rest of this season, the sagging Cardinals (4-8) have their own troubles at the position. Ryan Lindley was ineffective in his second NFL start as Arizona lost its eighth straight game after a 4-0 start.
Arizona finished 0 for 15 in third-down situations.
Lindley was harassed by a Jets defense that was terrific in keeping the Cardinals out of the end zone, taking advantage of a rookie quarterback making his second NFL start.
He went 10 of 31 for 71 yards and an interception while playing for Kevin Kolb, who missed his sixth straight game with a rib injury.
On McElroy's second drive of the game, he completed a swing pass to Kahlil Bell, who fumbled the ball and Daryl Washington recovered deep in Jets territory.
Lindley connected with Michael Floyd on a 16-yard gain, but things stalled again for the Cardinals and they settled for Jay Feely's 35-yard field goal that made it 7-6 with 10:39 left.
The only scoring in the opening half came on Feely's 48-yarder as time expired. The 10-play drive was helped by a fake punt on fourth-and-7 from the Cardinals 25 when Rashad Johnson took the direct snap and zipped downfield 40 yards for the biggest play of the game to that point.
After two incompletions and a 5-yard toss to Rob Housler, Feely an ex-Jet came out and broke the scoreless "slugfest."
Things got started on an ominous note for the Jets as Sanchez was intercepted by Rhodes on New York's first offensive play of the game. Ryan criticized Rhodes in his book "Play Like You Mean It" last year for being a "selfish" player, and New York traded him after the 2009 season.
Arizona couldn't take advantage as the Cardinals went for it on fourth-and-1 from the 17 and Beanie Wells lost a yard.
The Jets had a chance to get on the scoreboard on their next possession, but Nick Folk hit the left upright on a 46-yard field-goal attempt.
New York's next possession ended the same way its first did: with Rhodes picking off Sanchez again and looking over at Ryan and the Jets sideline.
Again, though, the Cardinals went three-and-out, but got the ball back on Sanchez's third interception of the half as Patrick Peterson grabbed the ball over Chaz Schilens.
Three plays later, Lindley gave it right back as LaRon Landry picked him off and returned it 24 yards to the Cardinals 37.
But, the drive stalled and Folk missed another attempt, this time dinging a 52-yard attempt off the right upright.