If the Mariners fail to become the first American League team since the 1974 Oakland Athletics to finish with an ERA under 3.00 — they started the day at 2.92 — they will probably point to Wednesday’s abomination by Erasmo Ramirez. Summoned from AAA Tacoma to make a spot start against Texas, Ramirez hurled the Mariners to an ugly 12-4 defeat, needing only 59 pitches, mostly fastballs over the heart of the plate, to get booed off the mound.

His brutal line: three innings, nine hits, 10 earned runs, grand slam, hit batter. By the time manager Lloyd McClendon mercifully applied the hook, eight of the nine Texas batters had a hit, and all nine had scored a run.

It marked the most earned runs allowed by a Seattle starter since Jason Vargas yielded 10 against Arizona June 20, 2012, and came within one of matching the franchise record of 11, shared by Jamie Moyer Aug. 9, 2000 vs. Chicago and Ryan-Rowland Smith July 27, 2010, also against the White Sox.

“It was just not very good,” McClendon generously said of Ramirez’s start. “He was up in the zone. I was encouraged after the first inning (three up, three down), but for some reason he started getting the ball up and that’s not a good thing against any team. He threw bad strikes. He just did not have it.”

Ramirez, whose ERA soared from 4.06 to 5.21, received the start when McClendon decided to push Felix Hernandez’s next outing to Friday, when The King will face the Washington Nationals, the first-place team in the NL East.

“It was the right thing to do,” McClendon said of starting the wildly inconsistent Ramirez, who has been up and down five times this season. “You can say I was a dumb SOB for doing it, but it was the right thing to do.”

Before Wednesday, the Mariners (72-60), whose wild card hopes took a hit (they are tied with Detroit for the second spot), had not allowed 10 or more runs in a game all season after doing so 21 times in 2013. They allowed three or fewer runs in 14 consecutive Safeco Field contests. Had they extended that streak to 15, they would have tied the 1967 Chicago White Sox for the longest such run in the American League since 1960.

Ramirez, who opened the season as Seattle’s No. 2 starter with Hisashi Iwakuma on the disabled list, made sure that didn’t happen. After the first, he unraveled. Tomas Telis ripped a three-run double as part of a four-run Texas second and Rougned Odor walloped a grand slam in the third as Ramirez yielded seven hits and eight earned runs before his pitch count reached 50.

“When you are home in front of your own crowd you don’t want it to get any uglier than that,” said McClendon. “The game’s over with, we got our butts kicked, it happens, and it hasn’t happened very often.”

The Rangers continued their bombardment of Ramirez in the fourth when Leonys Martin and Elvis Andrus singled and doubled, Martin scoring on an error in left by Dustin Ackley. That did it for Ramirez, forcing McClendon to give an inning each to a succession of five relievers to get through the game.

The only blemish on the pen: Martin’s two-run blast off Joe Beimel in the sixth.

Mike Zunino’s solo homer in the second, his 19th, briefly sliced Seattle’s deficit to 4-1, but that was buried by Odor’s grand slam. The Mariners collected two more runs in the sixth on a Kendrys Morales double that scored Ackley and Robinson Cano, and another in the ninth on Kyle Seager’s 20th home run. Otherwise, the Mariners didn’t have much offensively, seven hits off Colby Lewis, who entered with a 5.54 ERA, but threw his second complete game in a month.

Notes

James Paxton, a 5-0 winner Tuesday, was sent to the Rainiers Wednesday to make room for Ramirez on the roster, but will be recalled in time to make his next start, probably Tuesday in Oakland . . . Zunino’s 19th home run tied Seager for the team lead and matched Miguel Olivo’s 2011 single-season franchise record by a catcher. But Seager reclaimed the lead with his 20th, the third year in a row he has belted 20 or more . . . By dropping the series to the last-place Rangers, the Mariners fell to 21-18-5 in all series this season . . . McClendon said the Mariners will add six to nine players to the major league roster when Tacoma’s season ends Monday . . . The Mariners are 6-9 against Texas.

Next

After an off-day Thursday the Mariners host three with the Washington Nationals. RHP Felix Hernandez (13-4, 2.07) Friday opposes RHP Jordan Zimmerman (9-5, 2.93).