The daily bonfires lit by the Twins' bullpen wound up consuming their entire homestand. Now it threatens the whole season, and it's not clear who's going to put out this inferno.

An overstressed unit that coughed up the tying runs in the ninth on Sunday, surrendered 14 runs in two innings Monday, and turned a winnable game into a rout Tuesday, finally bottomed out in the Wednesday sunshine.

Trailing by only one run after six innings, the Twins turned to their bullpen and received nothing but misery: A six-run seventh decided the outcome, a three-run eighth added an extra poke in the eye, and human white flag Chris Gimenez surrendered two more runs in the ninth. Houston smashed six home runs and completed its more-than-convincing three-game sweep with a 17-6 dismantling at Target Field.

"We're happy these guys are out of here," starter Hector Santiago said of the Astros, who outscored the Twins 40-16 in three games and outhit them 47-30. "We're excited to be going on the road."

Because Cleveland lost to Oakland, the Twins survived the Houston series still in first place in the American League Central, although their lead shrunk from three games to two percentage points.

In the wake of this Astro assault and a 1-5 homestand, though, not everyone in the Twins' beleaguered bullpen is making the trip to California. Ryan Pressly, who surrendered the satellite George Springer put into orbit, was optioned to Class AAA Rochester after his ERA ballooned to 9.50. Jason Wheeler, whose second game in the majors didn't go any better than his first, was designated for assignment after allowing three runs.

The Twins will add righthanders Alex Wimmers and lefthander Randy Rosario on Thursday, according to a source, the latter coming up from Class AA. Rosario, 23, just converted to the bullpen last August and has a 1.90 ERA in 10 relief appearances at Chattanooga. Wimmers, the Twins' first-round pick in 2010, appeared in 16 major-league games last season, and had a 3.94 ERA with four saves for Rochester this year.

The Twins hope the new arms fare better than the others they've tried lately — but even they admit they're just spinning the roulette wheel now. "The fact you guys were [waiting] out there for awhile should tell you it's not too obvious," Twins manager Paul Molitor said after an unusually long postgame conference with his bosses to mull over the choices. "We're kind of circling through what we want to prioritize."

Fewer home runs would be a start. Pressly, Wheeler and Gimenez all gave them up Wednesday, making the Twins one of three AL teams with 31 allowed this year.

But that's nothing compared to the runs they're allowing: The Twins bullpen, ranked a mediocre but serviceable 18th in the majors only three days ago, now owns a 5.33 ERA — worst in the majors by far.

"It's hard to explain how that happens, but I do think there is some connectiveness to the last four days," Molitor said, dating back to their 15-inning, bullpen-clearing marathon Sunday. "These guys are tired, we get that. But there's time when you've got to dig a little deeper, when you know the full picture of what's going on with your team."

The Twins played without an ailing Miguel Sano for a second consecutive day, yet they still managed three home runs, including Brian Dozier's eighth of the season. Eddie Rosario and Jason Castro each homered in the Twins' three-run sixth, closing Houston's early four-run advantage to one. But that's when the bullpen took over for the Twins, and the Astros took over the game.

Springer was the first to sample the relief corps' offerings, and he absolutely devoured it, sending a middle-of-the-plate fastball from Pressly hurtling toward outer space.

"I was in shock. I've never seen a ball hit that hard in my life," said Carlos Correa, who clobbered a homer himself, too. "It's not really where it landed, it was just the way it sounded, the way it came off the bat. It just skyrocketed."

The 467-foot homer, Springer's second in a 4-for-4, four-run, six-times-on-base day, was the fourth-longest in Target Field history, eclipsed only by Jim Thome (twice) and Nelson Cruz.

It also brought Springer's career numbers at Target Field to 19-for-43 (.442) with five home runs in only 10 games.

"That's a good team that's on a roll. But we're good enough to bounce back," Dozier said.

"It's easy to talk about all the hiccups these last three or four games, but let's not lose sight of the fact we're still a first-place team entering June, too."