ST. LOUIS (AP) -- Christian Friedrich's first start since the All-Star break was much like the last few, even with three additional days of rest.

The San Diego Padres lefty didn't work deep into the game and lost his fourth consecutive outing in a 10-2 setback to the St. Louis Cardinals on Monday night.

"My slider was probably my best pitch, but it was hit or miss," Friedrich said. "If you don't establish the fastball, you're not going to have a good day."

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Friedrich (4-6) gave up four runs -- three earned -- and six hits in 5 1/3 innings. He had five walks, two more than he'd totaled the previous three starts.

"Even the outs I was getting, I was falling behind the hitters," Friedrich said. "Same old story. Having a feel for all four pitches would help out."

Friedrich has allowed 15 earned runs in 20 1/3 innings during the losing streak.

"He didn't have his command from the first inning on," manager Andy Green said. "It was a battle getting to the bullpen and getting him to the sixth."

Matt Kemp homered for the Padres, coming off a sweep at home over the NL West-leading Giants. The Padres have homered in a franchise-record 16 consecutive games.

But they also struck out 15 times, including all four at-bats for second-place hitter Wil Myers.

"I don't think anybody wants to go up and have flailing at-bats like we had to a certain extent today," Green said. "But it's just one game."

Mike Leake had his second straight double-digit strikeouts game with no walks, joining Bob Gibson as the only Cardinals to accomplish the feat.

Leake (7-7) struck out a season-best 11, one shy of his career high, and allowed one run and six hits in six innings. He fanned 10 over seven innings in a victory at Milwaukee on July 10.

Gibson accomplished the feat in his final start of the 1968 regular-season and his first in 1969, according to the Elias Sports Bureau.

Leake has four career double-digit strikeouts games and is the first Cardinals pitcher with 10 or more in consecutive starts since Lance Lynn in 2012.

Pinch hitter Matt Adams' two-run double keyed a four-run sixth inning. Randal Grichuk and Jedd Gyorko connecting in consecutive at-bats in the seventh, and Stephen Piscotty homered into Big Mac Land in the third deck in left in the eighth. Adams is 9 for 21 with two homers and eight RBIs as a pinch hitter.

Rookie Aledmys Diaz added an RBI triple, and Stephen Piscotty had a run-scoring single in the sixth-inning rally that put St. Louis ahead 6-1. Diaz also singled and walked and has reached safely in a team-high 22 consecutive games.

ROSENTHAL MOPUP

Cardinals manager Mike Matheny said former closer Trevor Rosenthal won't get any duty in "high-leverage situations" for the time being. Rosenthal retired the side in order in the ninth.

TRAINER'S ROOM

Padres: OF Jon Jay (right wrist) expects to get his cast off in about two weeks, and then a rehab will follow.

Cardinals: 3B Jhonny Peralta (sore thumb) was not in the lineup. He was taken out in a double switch on Sunday. OF Matt Carpenter (oblique) and 1B/OF Brandon Moss (ankle) played light catch together.

UP NEXT

Padres: San Diego has won eight of the last 12 starts of Colin Rea (5-4). He had no decision his last time out, allowing four runs in 4 2/3 innings on July 6 at Arizona.

Cardinals: Carlos Martinez (8-6) leads the majors with a .189 opponent's batting average and has allowed just one extra-base hit to a right-handed hitter.