Tua Tagovailoa had help from a less-heralded rookie while Justin Herbert struggled against a blitz-happy defense.

The surprising Miami Dolphins earned their fifth consecutive victory, beating the Los Angeles Chargers 29-21 Sunday.

Salvon Ahmed, making his first career start, ran for 85 yards on 21 carries and scored a 1-yard touchdown on Miami’s first play. The undrafted Ahmed filled in with two other running backs injured and sparked a ground game ranked fourth-worst in the league.

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Herbert threw a costly interception and was outplayed in the matchup of high draft picks by Tagovailoa, who passed for 169 yards with two scores and improved to 3-0 since taking over for Ryan Fitzpatrick. Herbert struggled against Miami’s blitzing defense and threw for a season-low 187 yards.

The Chargers were also outplayed on special teams, where they were hurt by two mistakes that allowed Miami to take a 14-0 lead.

The Dolphins (6-3) have their best nine-game record since 2001, and under second-year coach Brian Flores they’ve won more games than in all of 2019. The Chargers (2-7) dropped their third game in a row and have their worst record at this point in a season since 2015.

Keenan Allen had just three receptions and Mike Williams had two for Los Angeles.

Chargers punter Ty Long bobbled a snap and had his kicked blocked to set up the game’s first score on Ahmed’s short run. Quenton Meeks was offside on a field goal attempt by the Dolphins, giving them a first down that led to a touchdown.

The Dolphins were up 17-7 at halftime, increasing their NFL-best first-half point differential to plus-74.

Miami’s Jason Sanders made field goals of 50, 35 and 49 yards but missed from 47, ending his streak of 22 in a row. Jakeem Grant, the NFL leader in punt return yards, helped the Dolphins’ field position with three runbacks for 57 yards.

Miami’s Emmanuel Ogbah had a full sack for the sixth game in a row, and on the next play Xavien Howard picked off Herbert for his fifth interception of the year to set up Miami's final touchdown.

An onside kick recovery helped the Dolphins seal the win.

Chargers linebacker Kenneth Murray Jr. also let a potential interception slip through his hands, and three plays later Miami kicked a field goal for a 20-14 lead.

Miami has now scored at least 21 points in seven consecutive games, the team’s longest such streak since 2001-02.

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MIAMI'S LONE TURNOVER

The Dolphins were at the Chargers 9 and poised to build on a 14-0 lead when they lost a fumble on a bad snap by Ted Karras. Nick Vigil made a 44-yard return before Tagovailoa tackled him, and Herbert scored on a fourth-down sneak to make it 14-7.

INJURIES

Dolphins: LB Kyle Van Noy (hip) left the game in the first half. Miami was without DT Christian Wilkins and four assistant coaches because of COVID-19 protocols.

UP NEXT

Dolphins: Miami plays next Sunday at Denver for the first time since 2014.

Chargers: They play the second of three consecutive games against the AFC East when they host the New York Jets on Sunday.