TORONTO -- As the A’s have sunk deeper and deeper in the playoff race over the past few weeks, their bullpen has taken the brunt of the criticism for its inability to keep games close. The root of those bullpen woes, however, might stem from issues within the starting rotation.

After a competitive first two games that were tightly contested to the end, the A’s went down quietly in Sunday’s 8-0 loss to cap a three-game sweep at the hands of the Blue Jays at Rogers Centre. The series finale got out of hand early, with starter Cole Irvin lifted in the third after getting tagged for seven runs on eight hits over 2 1/3 innings.

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Entering the three-game series in Toronto three games ahead of the Blue Jays in the American League Wild Card standings, the series ends with both clubs now trailing Boston by four games for the second AL Wild Card spot.

“We’re in the last month here,” Irvin said. “We believe in the locker room that this is a playoff team. We’re talking to each other like we are. There’s no lost conviction in this team. We’re fighting for each other every day.

“Today was clearly on me. I didn’t give our team a chance to get back into that game.”

The A’s have dropped 14 of their last 20 games. Several of their losses over that stretch have been the result of bullpen shortcomings. However, those relievers have been pressed into action early and often in that time due to short outings like the one produced by Irvin, whose 2 1/3 innings pitched Sunday marked the shortest outing of his Major League career.

Irvin has navigated through an up-and-down first full season in the big leagues. With his 151 1/3 innings in 2021 well past his combined innings total over the prior two years, fatigue certainly could come into play. After allowing a season-high three home runs his last time out in Detroit, Irvin’s long ball issues crept up again on Sunday with two more given up, including a three-run blast to Alejandro Kirk that spelled the end of his outing.

Over his last eight starts, Irvin is now 2-5 with a 6.10 ERA. He’s pitched fewer than five innings in four of those starts.

“I think it’s more just a bad game for him,” A’s manager Bob Melvin said. “It’s not like he’s a really hard thrower. He’s more of a touch-feel guy with the sinker and changeup. I think everybody is in the same boat this year on every team as far as fatigue. The difference is, we’ve had guys pitch the entire season. We’ll see next time out. But overall, he’s been good for us.”

Following Sunday’s loss, A’s starters have now completed five or fewer innings in 14 of the last 22 games. If getting back into a playoff spot is in the cards over these final 25 regular-season games, righting the pitching ship is going to be essential.

Despite what ended up a 2-4 road trip, with Sunday’s loss dropping the A’s out of second place in the AL West for the first time since June, Melvin insists that a turnaround is coming. Perhaps as soon as Tuesday, when the club returns to Oakland for the start of a three-game set with the White Sox.

“I think the best part of our season is yet to come. I really do,” Melvin said. “I think we’re gonna get home, we’re gonna play our best stretch of baseball and get on a run before the season is over. Then we’ll have two teams that we need to beat there at the end.”

The basis of Melvin’s optimism comes from an offense that has started to perform up to its capabilities, Sunday’s game notwithstanding after Oakland ran into AL Cy Young candidate Robbie Ray and mustered just two hits. Prior to that, the A’s were batting .296 with 11 homers and 41 runs scored through the first five games of the road trip.

“Throw away today,” Melvin said. “They out-hit us and out-pitched us. We don’t have too many games like this. But I think the fact that the offense is coming around and swinging the bat a lot better is one of the reasons I’m encouraged. Our pitching has been consistent, less for a little stretch right now. I think it’s gonna match up from here on in.”