HOUSTON -- For Daniel Vogelbach, round numbers are nice. So are roundtrippers, as the Mariners’ first baseman cranked his 30th home run of the season on Friday in a 7-4 loss to the Astros at Minute Maid Park.

Vogelbach became just the seventh Mariner to combine 30-plus home runs with 80-plus walks in a season, joining the impressive list of Hall of Famers Ken Griffey Jr. and Edgar Martinez, Jay Buhner, Alex Rodriguez, Gorman Thomas and Richie Sexson. Griffey and Buhner each reached those totals twice.

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Vogelbach is the 15th Mariner to reach the 30-homer mark in a season, but he’s not ready to stop yet, with 20 games remaining.

“It’s a good mark, but there are plenty of games left,” Vogelbach said. “There’s more to do. I’m not OK with just 30.”

It’s an impressive total already for a 26-year-old who came into the year with just four Major League homers to his name in 61 games over three previous seasons, during which he bounced back and forth between Seattle and Triple-A Tacoma.

“That’s a heck of a year,” said manager Scott Servais. “I said to him two or three weeks ago, when he was struggling big-time, if we thought when we left Spring Training that he’d have the season he’s having, we’d have all signed up for it. Not just the power, but he understands the strike zone. And he’s done pretty well at first base. He’s gotten better over there.”

Vogelbach walked once as well, hiking his total to 85. That’s almost twice as many as Domingo Santana, who is second on the club, with 49.

But Vogelbach’s opposite-field blast leading off the sixth against Astros reliever Joe Biagini wasn’t enough to turn the tide for the Mariners, who are now 1-14 against the American League West leaders and 0-8 at Minute Maid Park.

Vogelbach’s second homer in his past five games was a welcome sight, however, for a Mariners team that would like to see the burly slugger pull out of a midseason slump and finish his first full year in the Majors on the upswing.

“He’s starting to get it back again,” Servais said. “He really struggled after the All-Star break, but he’s made some adjustments, he’s narrowed up his stance a little bit and getting through to some balls, which he needs to do. He hit the tar out of that ball tonight.”

Vogelbach had an impressive .238/.375/.505 line with 21 homers and 51 RBIs in the season's first half, and was named to the American League All-Star team.

Post-break, he’s hitting .177/.301/.404 with nine homers and 23 RBIs after going 1-for-3 with his homer on Friday.

Pitchers have figured out how to better attack him with off-speed offerings, and he’s struck out 49 times with 24 walks in the season's second half after totaling 79 strikeouts with 61 walks in the first.

But he jumped on Biagini's first-pitch fastball in the sixth and deposited it in the Crawford Boxes in left field, an impressive shot to the opposite field, to cut Houston’s lead to one run.

“I’m just continuing to put swings on balls and whatever happens after that, you can’t control,” Vogelbach said. “The past month and a half, obviously, hasn’t gone the way I want, but it’s baseball. You go through skids and you just have to keep going and believe that eventually you’re going to get out of it.

“I believe I’m a good hitter. I believe in myself and the work I put in. I knew eventually it was going to happen, you just never know when.”