And the Cincinnati cornerback made the most of it.
Newman returned the interception 54 yards for the early score and the Bengals went on to beat the Arizona Cardinals 19-13 on Sunday night.
"He pretty much threw it right to me," Newman said. "It wasn't like I did anything, just an errant throw on his part.'
Fitzgerald blamed himself.
"I didn't break across the corner's face and I've got to do that," he said, adding that he can't let the quarterback "hang out to dry."
But it will look like Palmer's mistake.
"That's what it is in the quarterback's world," Arizona coach Bruce Arians said.
It was that kind of night for the Arizona offense against a Bengals' defense that ranked second in the NFL last season.
"We had a number of things that were just off," Palmer said, "from overthrows to missed opportunities, some funky things that happened on a couple of routes and some drops."
Mike Nugent added field goals of 48 and 36 yards for Cincinnati (1-2).
The Cardinals (1-2) got their lone touchdown on a 30-yard pass from backup Drew Stanton to rookie John Brown, who stretched out for a diving grab in the end zone with 1:29 left in the third quarter, tying it at 13-13.
Cincinnati backup Quinn Sharp kicked field goals of 34 and 51 yards after that for the deciding margin.
"We kind of gave it to a pretty good football team," Arians said, lamenting the missed opportunities, "and you just can't do that, especially at home."
The Bengals' Andy Dalton completed 13 of 21 passes for 183 yards. Palmer was 7 of 19 for 92 yards. Larry Fitzgerald caught five of Palmer's throws for 71 yards.
Both teams played their starters the entire first half.
Palmer was facing the team he was with for the first eight years of his NFL career before an acrimonious split sent him to Oakland. Dalton replaced Palmer as a rookie in 2011.
Cornerback Leon Hall said "it means something to me, for emotional reasons I guess" to hold Palmer, his former teammate, without a touchdown.
"But really," Hall said, "I'd feel almost the same way regardless who we were playing. This was what they call a rehearsal game. ... This builds some momentum for (the opener against) Baltimore."
Bengals owner Mike Brown was taken to a Phoenix hospital before the game for what was termed a "minor" health problem. The team said he was to return to Cincinnati and did not attend the game.
"I guess the good thing is everyone acted very quickly to get things headed in the right direction very fast," Bengals coach Marvin Lewis said, adding that Brown would have preferred to have kept the incident quiet. "We're happy that, hopefully, everything is going in the right direction and hopefully he'll get back with us very quickly."
Cincinnati inside linebacker Vontaze Burfict left the game in the first quarter with a hamstring injury.
On the Cardinals' second possession, it was third-and-7 from the Arizona 40 when Palmer fired a pass intended for Fitzgerald. But the errant throw went right to Newman, who evaded a couple of early would-be tacklers and outran everyone else to the end zone.
The Arizona starters' biggest offensive threat came on their first possession of the second quarter. The defense forced the Bengals to punt from their 6-yard line, giving the Cardinals good field position at the Cincinnati 41.
Statistically, at least, the Bengals' starters had the advantage, outgaining Arizona 198-141 in the first half.
"On defense, we had some negative plays," Lewis said, `but overall the effort -- and of course the point total -- was what you are looking for."
Cincinnati DT Geno Atkins played two series, his first game action since tearing an ACL and missing the last seven games a year ago. ... Bengals rookie guard Trey Hopkins was carted off the field in the fourth quarter with a right shin injury. Moments later wide receiver James Wright left via cart with a concussion. Guard T.J. Johnson became the third Bengal carted off the field in the fourth quarter. ... Arizona was without starting inside linebacker Kevin Minter (pectoral muscle) and guard Jonathan Cooper (toe).
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