Emmanuel Rivera knocked in four runs Tuesday night and Tyler Wells won his first start in more than 16 months as the visiting Baltimore Orioles kept the San Diego Padres' recent skid going with a 6-2 victory.

Wells (1-0), who has been sidelined since early last season after undergoing elbow surgery, allowed five hits over five innings in an 85-pitch effort. Wells gave up two runs, walked none and fanned four.

Yu Darvish (3-5) absorbed the loss after permitting six hits and four runs, three of them earned, in four-plus innings while walking two and whiffing six. It was the seventh loss in nine games for San Diego (76-63), which remained 2 1/2 games behind the first-place Los Angeles Dodgers in the National League West.

Jeremiah Jackson got Baltimore (63-76) on the board two batters into the game, lining a curveball over the left field wall for his fourth homer of the year and his second in as many games.

Rivera made it 3-0 in the third when he laced the first of his two two-run singles over shortstop Mason McCoy to score Ryan Mountcastle and Colton Cowser, who had both singled with one out.

The Padres got their runs with one swing of Luis Arraez's bat in their half of the third. He cracked a two-run homer over the right field wall, his seventh of the year. But they simply couldn't produce a clutch hit after that, going 1-for-8 with men in scoring position.

Rivera restored a three-run advantage for the Orioles in the fifth with a two-run single off reliever David Morgan to score Gunnar Henderson and Mountcastle. Jackson capped the scoring in the eighth with a chopper to short that chased Dylan Beavers home.

San Diego filled the bases in the seventh with one out via walks to Jake Cronenworth, pinch hitter Ryan O'Hearn and Fernando Tatis Jr. But Rico Garcia then took over on the mound and quashed the rally by fanning Arraez and inducing a fielder's-choice bouncer from Manny Machado.

Rivera, Mountcastle, Cowser and Jackson Holliday each bagged two of Baltimore's 10 hits.