HOUSTON -- What has been a marvelous career for Félix Hernández with the Mariners continued heading toward a painful ending as the veteran right-hander was roughed up by the Astros in a 21-1 loss Sunday at Minute Maid Park.

Hernandez, making his fourth start since coming off a three-month stint on the injured list with a sore right shoulder, gave up 11 runs (seven earned) on seven hits with two walks and a hit batter in just two-plus innings as he fell to 1-6 with a 6.56 ERA in 12 outings.

The former American League Cy Young Award winner is in the final days of a contract paying him $27 million this season, which is his 15th year in a Mariners uniform. He’s in line to make three more starts, beginning Saturday in Seattle against the White Sox.

“It’s been a strain these last two starts. Just grinding and grinding,” Hernandez said. “I just have to keep doing my thing, and we’ll see what’s going to happen next. [The remaining starts are] very important. It means a lot for me to go out and compete the way I can compete, every five days.”

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Manager Scott Servais said Hernandez will continue getting opportunities in the closing weeks for a Mariners club that is now 58-86.

“Certainly, we’ll give him the ball and give him a chance to go out,” Servais said. “You’ll see it for a couple innings, he gets it going. It’s just the consistency. Getting through the lineup two or three times is a challenge some days.”

Hernandez wasn’t the only Mariner who was struggling against the front-running Astros, as Seattle managed just one hit -- a home run by Shed Long in the fourth -- off standout right-hander Gerrit Cole as Houston completed a four-game series sweep. Cole struck out 15 Mariners in eight innings, becoming the second pitcher in MLB history (along with Pedro Martinez in 1999) to whiff 14-plus batters in three straight starts.

The 21 runs were the second most ever surrendered by the Mariners, one shy of the club record set in a 22-10 loss in Boston in 2015. The Astros racked up 22 hits -- including 11 doubles and two home runs -- off five Seattle pitchers. The 11 doubles were the most ever allowed by a Mariners team, breaking the record of nine given up to the Brewers on Sept. 29, 1992, and the most ever hit by the Astros in a single game.

“You take it and learn from it,” said Long, one of four rookies in the Mariners’ starting lineup. “You have good days and then you have learning days. You learn from everything they do. The way they play the game, the way they handle their at-bats, everything. It’s a learning experience.”

The Mariners are 1-16 against Houston this year, with two more games remaining later this month in Seattle, and finished the year 0-10 at Minute Maid Park. The 16 wins are the most the Astros have ever totaled in one season against an opposing team. They were 15-3 against the Giants in 1985.

The 20-run margin made this the most-lopsided loss in franchise history, breaking the former record of 17 in a 20-3 defeat at Detroit in 1993. The Mariners have lost six games by 13-plus runs this season, the most by any MLB team since the 1955 Kansas City A’s.

“We got hammered,” said Servais. “What can you say? Gerrit Cole is one of the top pitchers in the league, and you certainly saw it today. He’s been really, really good -- not just against us, against the whole league. We knew coming into the game, you’re up against it and hoping to hold them down, but that just wasn’t the case.”

Hernandez retired the first five Astros in order before walking Kyle Tucker and giving up a double to Abraham Toro. He appeared to be out of the second without any damage until Dee Gordon -- making a rare start at shortstop -- booted what would have been an inning-ending grounder by Martin Maldonado.

That misplay allowed two runs to score, and Jake Marisnick ripped Hernandez’s next pitch -- a 90-mph fastball down the middle -- for a 432-foot homer to left to give Houston four unearned runs in that frame.

Then, the wheels came completely off in the third when Hernandez gave up five hits -- all doubles -- along with a walk and a hit batter without recording an out. By the time reliever Erik Swanson allowed both inherited runners to score on a three-run blast by George Springer, Hernandez had been charged with seven runs in the inning.

“I was fine … until the third,” Hernandez said. “I fell behind a lot of times, had to throw strikes and they hit the ball pretty hard. That’s a pretty good lineup. You can’t miss.”

Houston wound up with nine runs on eight hits -- including six doubles and a homer -- in that inning alone, rolling to a 13-0 lead.

The Astros lead the AL West at 94-50, while the Mariners have lost six straight in falling to a season-low 28 games under .500.