Twice in the second quarter, Ryan Tannehill had the ball in his hands with the chance to give Miami a first-half lead and quiet the Superdome crowd.
Both times, the young Dolphins quarterback turned it over, the crowd went wild and the Saints cashed in.
Tannehill fumbled the ball away once and threw three interceptions, which wasn't nearly good enough to keep pace with Drew Brees in a 38-17 loss Monday night.
"We're not happy. Obviously you don't want to come out and perform like that," Tannehill said. "But you look at it and there are things you can correct."
He finished with 249 yards passing and a touchdown to Charles Clay. That paled in comparison to Brees' 413 yards and four TDs.
Miami's running game appeared to be getting going for the first time this season early on, but the Dolphins had to abandon it the more they fell behind, and the Saints turned up their pass rush, sacking Tannehill four times in the second half.
"I just don't feel that team was as good as everybody was saying they were," Saints outside linebacker Junior Galette, who had one sack, said of Miami. "We just abused the offensive line all game."
Miami's Lamar Miller had 62 yards rushing on 11 carries, including a 5-yard scoring run late in the second quarter that made it 14-10, but the Saints began to run away with the game after that.
Tannehill's first turnover came when he tried to scramble up the middle and was stripped by linebacker Curtis Lofton. Safety Rafael Bush recovered on the New Orleans 38. That set up a drive that ended with Jimmy Graham's leaping, juggling catch as three defenders, including Jamar Taylor and Brent Grimes, converged on him.
"Both Brent and I were right there on the coverage and we reacted when the ball was up in the air, but it was angled such that (Graham) went up and made a great play and came down with it," Taylor said. "It was obviously a big play for them and gave them momentum in the first half."
Later in the half, Jabari Greer intercepted a pass intended for Brian Hartline and returned it 22 yards to the Miami 23. Several plays later, Darren Sproles made a catch along the left sideline, spun away from a converging defender and scored his second touchdown with 55 seconds left in the half to make it 21-10.
In the third quarter, Brees' touchdowns of 4 yards to tight end Benjamin Watson and 43 yards to Graham made it 35-10, and what had been a highly hyped game of two unbeaten clubs had turned into a rout — and a sobering blow to Miami (3-1).
"We'll find out a lot about the team we have by the way we come back tomorrow," Miami coach Joe Philbin said.
Miami receiver Mike Wallace had only three catches for 24 yards, far short of what he was hoping for in his return to his hometown.
"This was definitely not the outcome we were looking for," Wallace said. "We came in with high expectations and it was a close game early on. But they scored a few touchdowns in a row and that forced us to play catch-up."
A week earlier, the Dolphins were able to mount a comeback at home against Atlanta. Doing so again proved much harder in the Superdome, particularly with Brees completing 30 of 39 passes and marching the Saints to 465 total yards.
"I felt like we found our rhythm," Brees said. "Every time we touched the ball, it felt like we were going to go down and score points."
Two of Brees' touchdowns went to Graham, a former Miami college basketball and football player, as the tight end had at least 100 yards receiving for the third straight game.
"He plays out of this world," Graham said. "This team is so dynamic, we have so many weapons and Drew knows exactly where to go with the ball."
Miami had little answer for Sproles, who made seven catches for 114 yards.
Sproles' 5-yard scoring run on the game's opening series gave the Saints a lead they would not relinquish en route to their first 4-0 start since their Super Bowl championship season of 2009. It also further accentuated what a turnaround the Saints have made since coach Sean Payton served his bounty ban last season, which New Orleans opened with four losses.
"We like this a lot better," Brees said of the 4-0 start. "Everything that could have gone wrong for us went wrong. Fortunately we're having the ball bounce our way this year. We're playing good football."
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