Six months later, in his debut as an NFL starter, he beat the reigning Super Bowl champions — with some luck and a lot of help from his defense.

The rookie from BYU, optimistically listed at 6 feet 1 inch, survived some brutal hits to complete 17 of 27 passes for 168 yards, and the Arizona Cardinals upset the New Orleans Saints, 30-20, yesterday.

Hall threw an interception that led to an early Saints field goal. He also fumbled twice, but both turned out to be key plays for Arizona (3-2). The first was run 2 yards by Cardinals tackle Levi Brown for a touchdown. Guard Alan Faneca pounced on the other for a 10-yard gain and a first down.

It was an uneven performance, but there was no doubt the extremely confident and ultra-competitive Hall earned the respect of his team.

“I need to fix my mistakes,’’ he said, “but I think those guys trust me and I think when they look at me they know we have a chance to win.’’

Cardinals linebackers Paris Lenon and Joey Porter used the same phrase to describe their new starting quarterback: “just a tough little guy.’’

Arizona’s defense, awful in a 41-10 loss at San Diego a week earlier, “deserves all the credit’’ for the win, Hall said.

The Cardinals intercepted Drew Brees three times and converted two turnovers by the Saints (3-2) into touchdowns. He had been picked off just twice in the first four games.

Kerry Rhodes returned Ladell Betts’s fumble 27 yards for a score and, with 10 seconds to play, Dominique Rodgers-Cromartie returned an interception 28 yards for the clinching TD.

“We finally put a good effort together,’’ Rhodes said. “It wasn’t perfect, it wasn’t pretty at times for us, but we played as complete a game as we’ve played so far.’’

New Orleans outgained the Cardinals, 373-194, but couldn’t overcome four turnovers.

Brees, who entered the game completing an NFL-best 74 percent of his passes with just two interceptions, threw for two touchdowns.

His 35-yard TD pass to Robert Meachem cut Arizona’s lead to 23-20 with 1:49 to play. But Larry Fitzgerald, who caught seven passes for 93 yards, recovered the subsequent onside kick for Arizona.

New Orleans had one final shot, getting the ball at its 9-yard line with 24 seconds to play. But Rodgers-Cromartie picked off Brees’s pass and weaved through would-be tacklers for the final score.

Ken Whisenhunt called it one of the most satisfying victories in his three-plus seasons as Arizona coach. He sees better days ahead.

“We didn’t run the ball as we have been today and that’s because they tried to stop the run and make us beat them throwing the football,’’ Whisenhunt said. “I’m not scared to do that with Max. We’re going to be able to expand on our offense, do more things, as Max gets more comfortable with it, which is going to make it harder to defend us. So I see us evolving. I think today was just the tip of the iceburg.’’

The Saints’ red-zone problems continued. New Orleans made four trips there and managed one touchdown. Twice the Saints settled for field goals. Another time, John Carney missed a 29-yarder that would have given his team a 16-13 lead in the third quarter.

Saints coach Sean Payton said there were “some things that are positive about how we played.’’

“But there were too many things that are going to keep us from winning games,’’ he said. “We failed again in the red zone to be as efficient as we like. Turnovers, kick coverage units, even the penalties are disappointing. If we are going to expect different results we have to play better than today.’’