SAN DIEGO -- After a three-year absence, Clayton Richard returned to the San Diego Padres on Aug. 6.

But it is not the exact same Clayton Richard.

The 6-foot-5 left-hander, who turns 33 on Monday, has changed his delivery and his approach. And the alterations are paying dividends for the Padres.

Richard pitched seven scoreless innings Thursday night, and rookie second baseman Ryan Schimpf drove in four runs with a double and a homer as San Diego defeated the Colorado Rockies 14-1 in the opener of a four-game series at Petco Park.

Richard (2-3) allowed six hits and two walks with eight strikeouts in his seventh appearance (fifth start) since signing with the Padres on Aug. 6. Richard, who previously pitched for San Diego from 2009-13, lowered his ERA as a Padre to 1.15 over 31 1/3 innings.

Since having AC joint surgery at the end of his first tour with the Padres and thoracic outlet surgery the following February, Richard has lowered his arm angle and developed a sinker to go with his higher-angle fastball.

"It is different," San Diego manager Andy Green said after Richard improved to 2-2 with the Padres with his second scoreless outing in a three-start span.

"His ball is sinking and he's getting ground-ball outs. And he can still throw the fastball up in the zone. It's a good recipe."

Richard said, "I'm smarter. I'm taking things easier. Less is more. I did move my arm slot, but I'm staying relaxed. And tonight I was consistently down in the zone."

In addition to the eight strikeouts, Richard got 11 outs on grounders Thursday. Only one out was hit to the outfield.

"He's definitely deceptive," Rockies manager Walt Weiss said. "It looks like his fastball has come back. The velocity is creeping up there again, and he's got a lot of movement."

Meanwhile, Schimpf continued his torrid extra-base hitting since he made his major league debut with the Padres on June 14. He hit his 15th double and 18th homer Thursday night. After 214 at-bats, Schimpf has 50 hits, with 38 going for extra-bases.

Schimpf, Travis Jankowski, Yangervis Solarte and Alex Dickerson all had two hits for the Padres. Jankowski, Derek Norris and Luis Sardinas each drove in two runs. Dickerson scored four runs.

Norris hit a two-run homer in the eighth, his first home run since July 10, and he scored three times. However, in the ninth, the catcher had to leave the game after taking a foul ball off his right clavicle.

Rockies shortstop Cristhian Adames, whose two-out error led to seven unearned runs in the Padres' third, homered with one out in the ninth to deny the Padres their most lop-sided shutout win in franchise history.

Schimpf's three-run homer capped the seven-run rally that broke up a scoreless tie.

Rockies starter Jeff Hoffman (0-3) should have been out of the inning without allowing a run.

Hoffman walked Sardinas to open the third and personally tagged out Richard on a sacrifice bunt that allowed Sardinas to take second. Adames then fielded a grounder and threw out Jankowski.

Had Adames done the same thing on the ensuing grounder by Jon Jay, the game would have remained scoreless. But Jay's grounder kicked off Adames' glove for an error that allowed Sardinas to score the game's first run.

More important, the error opened the flood gates. Jay was the first of seven straight Padres to reach base.

"I didn't lose focus," Hoffman said. "I just think a couple pitches leaked back over the plate and found barrels. The error doesn't mean anything. That stuff happens. You just gotta go out and make the next pitch and get out of it."

Weiss said, "The error certainly hurt, but you gotta be tough about picking that guy up. You have to put the inning down at some point. Hoffman just needs to get in better counts. He's got the weapons to be real good. He's going to be a good one."

Wil Myers, Solarte and Dickerson followed Adames' error with sharp singles -- the last two driving in runs to make it 3-0. Schimpf then hit the first pitch he saw 408 feet to make it 6-0.

Still, it wasn't over. Norris drew a walk, stole second and scored on Sardinas' single to make it 7-0.

Hoffman was mercifully removed from his fourth major league start, having allowed seven runs -- none of them earned -- on six hits and two walks in 2 2/3 innings.

The Padres added three more runs on just one single in the fifth. Rockies right-handed reliever German Marquez, who made his major league debut in relief of Hoffman, issued three straight walks to open the inning. Dickerson scored on a grounder to first by Richard. Schimpf and Norris scored on a two-out single by Jankowski.

The Padres made it an even dozen in the bottom of the sixth against right-handed reliever Matt Carasiti. Solarte doubled with one out, advanced to third on a single by Dickerson and scored on Schimpf's double halfway up the wall in right. Dickerson scored on a bases-loaded walk drawn by Sardinas.

NOTES: Padres RHP Jarred Cosart will miss at least one start after sustaining both a right hamstring and right groin strain Wednesday night when he landed awkwardly while covering first base on a grounder. The severity of the injuries won't be known for another three or four days. Cosart's injury could alter the Padres' plan to use a six-man rotation for the rest of the season. ... The Rockies activated RHP Jason Motte from the disabled list Thursday. Motte had been out since July 27 with a rotator cuff strain. The addition of Motte gives Colorado a 37-man roster that includes 13 relief pitchers.