SEATTLE -- There is still a lot of baseball left before San Diego Padres starter James Shields might get a chance to live up to his "Big Game" nickname, but on Wednesday night he proved himself in crucial situations time and again.

Shields bounced back from two rough outings to lead the San Diego Padres to a 4-2 win over the Seattle Mariners on Wednesday night. He got out of jams in the first, second and fourth innings, showing manager Bud Black enough to keep him in after giving up back-to-back walks to open the sixth as his pitch count swelled to triple digits.

Shields got out of that as well.

"Shieldsy competed his (butt) off," Black said. "He made some pitches and showed why he's the pitcher he is."

Shields (5-0) struck out nine batters while allowing just one earned run over six innings, ending the Mariners' five-game winning streak. It was his best performance this month, despite the six hits and three walks he allowed.

"It was a grind today, for sure," Shields said. "I got out of some jams."

The only run on Shields came on a solo home run by Mariners shortstop Brad Miller in the fifth. Seattle (15-18) went 1 for 13 with runners in scoring position, with Miller breaking an 0-for-11 night with his second RBI of the game on a ninth-inning double.

"The positive is we got them out there," Mariners manager Lloyd McClendon said. "The negative is we couldn't get them in. That guy on the mound (Shields) had a lot to do with it, too... had him on the brink a few times. Just couldn't get the big hit today to get us over the hump."

Closer Craig Kimbrel came on in the ninth to earn his 10th save of the season for the Padres (18-17). Kimbrel allowed two hits and a run and now has a 5.93 ERA in 15 appearances.

Mariners starter Taijuan Walker (1-4) allowed just two earned runs and four hits in six innings but suffered the loss. Seattle was trailing 2-1 when he gave way to the bullpen to open the seventh inning, then former Mariner Abraham Almonte tacked on a run for the Padres with an RBI single off reliever Joe Beimel for a 3-1 San Diego lead.

"He competed well against a tough ballclub," McClendon said of Walker. "I was very pleased."

Padres third baseman Will Middlebrooks homered, while second baseman Cory Spangenberg added two hits, a run, an RBI and a stolen base for San Diego.

Seattle's Miller went 2-for-4 while driving in both of the Mariners' runs.

First baseman Logan Morrison had two hits for the Mariners, who had won the first five games of their homestand before falling Wednesday. Seattle right fielder Nelson Cruz went 1-for-4 but was held without a home run for the first time in his past six interleague games, dating back to last season. The five-homer streak in interleague play had matched a major league record.

Seattle struck out 14 times and left 10 runners on base in the loss.

Middlebrooks gave the Padres a 1-0 lead with a leadoff home run in the top of the third inning. San Diego went ahead 2-0 three batters later, when shortstop Alexi Amarista scored from third on a sacrifice fly from Spangenberg.

Shields gave up a leadoff single and a walk to the first two batters he faced but got out of that jam -- and struggled out of trouble again in the second and fourth innings.

The Mariners finally got on the board when Miller's two-out solo shot in the bottom of the fifth cut the San Diego lead to 2-1. That marked the 51st homer allowed by the Padres this season and the eighth Shields has given up over his three most recent starts.

"Honestly, I don't really care about home runs," Shields said. "I care about wins. I've never been a guy that doesn't give up home runs; I go out and compete."

Shields pitched his way into trouble again in the sixth, when he walked third baseman Kyle Seager and Morrison to start the frame. Black came out to talk to Shields, who then got a strikeout and inning-ending double play to finish off his night after 115 pitches and the Padres leading 2-1.

"I knew I was going to keep him in," Black said later of his visit to the mound. "We had to talk about something strategically. But I liked the way he was throwing."

NOTES: San Diego 1B/OF Wil Myers (left wrist) was not in the lineup for the second game in a row. The Padres sent him back to San Diego for further tests. Black said he expects to hear more before Thursday's game against Washington. ... The Padres are tied with Milwaukee for the most home runs allowed, with 51. ... Wednesday marked the final day of a nine-game, 10-day road trip for San Diego. ... Mariners RF Nelson Cruz went into Wednesday leading the AL in batting average (.349) and home runs (15) but was one RBI behind Oakland's Stephen Vogt (30).