Johnny Vander Meer is safe. Mike Pelfrey never is lately.

Joe Mauer spoiled Mike Fiers' attempt at matching Vander Meer's long-ago feat of back-to-back no-hitters Saturday night, and Pelfrey foiled his own attempt at recapturing the effectiveness that made him so valuable early in the season. Another gradual Pelfrey meltdown put the Twins in a four-run hole and resulted in an all-too-familiar 4-1 loss to the Astros at Target Field.

"He got through the first couple of innings," Twins manager Paul Molitor said with a shrug, "but got into a little trouble there with where he was locating his fastball."

Molitor sounded relatively upbeat, considering how common this problem has become. Twins starters have gone eight consecutive games without completing six innings. And Pelfrey remains the most unpredictable, most erratic, most capricious pitcher on the staff — an All-Star-caliber fireballer when he's on, a journeyman junkballer when he's not. He has pitched some of the Twins' best games of the season, and owns a spectacular 1.05 ERA in his six victories this year.

But in his eight losses, Pelfrey's ERA stands at 7.40.

"My last couple of starts, my command hasn't been great, and it just kind of continued," he said. "Against a team like this — their pitching is so good — I put these guys in a tough hole. That's on me. I didn't do very good."

Pelfrey gave up one hit to the first 11 hitters he faced, but six more to the next eight hitters, and the Twins could never recover. Robert Louis Stevenson dreamed up the two-faced Jekyll-and-Hyde character, but Pelfrey has perfected it on the mound. He leads American League starters (minimum 20 starts) in fewest home runs — seven, in more than 142 innings — yet the 125 singles he's surrendered are the third-most in the league.

Pelfrey departed in the fourth inning, after Luis Valbuena's two-run double and Jake Marisnick's RBI single gave Houston a 4-0 lead it never surrendered. That dropped Pelfrey's record to 1-6 since mid-June.

But the Twins' newly stabilized bullpen shows no strain from the heavy workload. Four relievers held the Astros without another run, contributing 5⅓ consecutive scoreless innings to the cause. Blaine Boyer, Neil Cotts, Casey Fien and Brian Duensing cleaned up after Pelfrey, with Duensing even overcoming a pair of errors to work out of trouble.

The early deficit was too much for a suddenly slumbering Twins offense, however. Five times they put the leadoff runner on base, and only once did they score.

"You try to take advantage. We got a couple of leadoff doubles from [Brian] Dozier, but it wasn't a get-'em-over situation," Molitor said. "You want to take advantage, but it doesn't always work out."

The Twins loaded the bases with no one out on a single and two walks in the fourth inning and scored a run on Trevor Plouffe's double-play grounder. But that's all that Fiers, who in his previous start pitched Houston's first complete-game no-hitter in 22 years, would allow. The Twins wasted a leadoff double in the sixth by Dozier, and they again didn't do anything in the seventh when they had two on and nobody out.

In fact, until Dozier doubled and Mauer singled to start the eighth inning off former Twins reliever Pat Neshek — another rally that produced no runs — the Twins had gone 20 consecutive innings without collecting two hits in any of them.

The Twins did see some excellent outfield defense, including two long running catches by center fielder Byron Buxton, plus Eddie Rosario's near-daily habit of throwing out a runner. Playing left, he collected his seventh assist in the past 15 games by throwing out Evan Gattis as he tried to stretch his RBI single into a double. Rosario's 13 assists are the most by any Twins outfielder since Michael Cuddyer's 19 in 2007.