HOUSTON -- Not even Luis Castillo at his best can beat Yordan Alvarez, let alone the Houston Astros, without a little help.

It looked like Castillo was delivering an encore of his brilliant performance in the Wild Card Series, blitzing the Astros’ hitters with velocity that ran and snapped in either direction. His 76 pitches thrown 97 mph or harder were more than any pitcher has thrown in an outing since pitch-tracking began in 2008.

Then, a bloop and a blast changed it all. The Mariners lost Game 2 at Minute Maid Park on Thursday night, 4-2, and fly home to Seattle down 2-0 in the ALDS, needing to win each of their next three games. Just to get their most dominant arm back on the mound in this series, which Castillo could do on short rest in a potential Game 5 on Monday, the Mariners will need to write another dramatic chapter at home.

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“You can't say enough about the job Luis Castillo continues to do on the biggest stages against some of the best lineups in the league,” said manager Scott Servais. “He was outstanding today. I thought our whole club really the last couple games here have competed as good as you can. We left it all out there.”

Five days after a blooper was the Mariners’ best friend, when J.P. Crawford’s double fell in shallow center in Toronto to tie the game late, it was their worst enemy Thursday. With two outs in the bottom of the sixth and Castillo cruising, Jeremy Peña’s single hung up in the air and dropped in shallow center field between Julio Rodríguez and Adam Frazier.

"I thought I had it,” Frazier said. “I look up and you see a truck running at you, you kind of hesitate, and that's what happened. I think he did the same, looking down. We've just got to communicate a little better.”

Two pitches later, Alvarez got a 98.3 mph sinker away and a couple of inches outside of the zone, and he launched it over the left-field wall to give the Astros the lead. You can count on one hand how many MLB hitters would take that pitch deep.

Castillo had a clear reaction on the field when that first ball dropped, of course, but said after the loss that there were no frustrations that carried over. His focus shifted immediately to Alvarez, and even with the star slugger’s presence at the plate, Castillo wanted to continue plowing forward.

“It's not just him, it's against any batter,” Castillo said through a club interpreter. “I always go with that mindset. If you're good, I'm good too. I came with the same plan of just getting him out, and he was able to make contact with that ball. But like I said, I'm going out there to get any batter out.”

The Mariners face a steep uphill climb now, and these Game 2 frustrations are only made worse by the fact that they happened to their ace. Castillo needed to be nearly perfect to win Game 2 with only two runs of support on five hits from his offense. Being perfect against a team as talented and playoff-tested as the Astros is rarely going to happen.

Alvarez has taken this series over. These first two games have been like watching an NBA star take over a playoff series, but it’s far more rare to see a single player tilt a series this dramatically in baseball. After his walk-off in Game 1 and go-ahead home run in the sixth, the Mariners intentionally walked Alvarez in the eighth with a runner already on first. They did that to get to Alex Bregman, a star in his own right, who promptly singled home an insurance run.

“I thought about Barry Bonds,” said Astros manager Dusty Baker. “That was some Barry Bonds-type stuff there. That's the ultimate respect. Bregman rises to the occasion too. That's why I have Bregman hitting behind Yordan, because all you need in that situation is a base hit. Right away I thought about [Bonds]. I've seen that a bunch of times, but not in a long time since Barry Bonds.”

The Mariners have to hope that the energy of their first home postseason game since 2001 forces some breaks back in their favor. Seattle will turn the ball over to George Kirby, and the entire effort over the next three days will be focused on getting Castillo back on the mound one more time.

Castillo didn’t get the help he needed in Game 2, but both he and the Mariners were close. Now, the ace is left to watch on, hoping for one more shot at the unstoppable force of Alvarez and the Astros.