One week ago, Steven Matz owned a 4-0 record with a 2.31 ERA and looked like the unexpected answer to the Blue Jays’ No. 2 spot in the rotation. His past two outings have gone in a different direction.

Matz allowed five runs, including two deep home runs, over five innings in Monday’s 5-4 loss to the A’s at the Oakland Coliseum, bumping his ERA up to 4.78. The truth lies somewhere in the middle, as it typically does with early swings in performance like this, but we’re now seeing what a variable Matz can be in this rotation.

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The left-hander was visibly frustrated in the dugout when manager Charlie Montoyo told him his night was done after the fifth. Matz felt like he was close to having his April stuff, and he wanted to do more.

“I know the bullpen has been working their butts off, and I want to go as deep into that game as I can there,” Matz said. “I didn’t do a good job of that tonight. I definitely wanted to go back out, that’s kind of my competitiveness.”

When the Blue Jays entered the season, it was understood that the rotation lacked high-end upside behind ace Hyun Jin Ryu. There were options, of course, in starters with potential like Matz, Robbie Ray or top prospect Nate Pearson. This is also part of the club’s natural progression, with frontline starting pitching being the next major priority as this talented roster takes shape. Injuries have mounted, though, which has added some urgency for the rotation’s healthy arms to perform.

“He’s a big part of our team right now,” Montoyo said of Matz. “His last two outings have not been that great, but the arm is there. We know it. He’ll get it back. I truly believe in that. He’s got the arm, and [pitching coach] Pete Walker is going to help him out. His next outing is going to be good. I just know that.”

There will be highs and lows, especially this early in a season. Ray has looked sharp lately, but he’ll have his off nights along the way, too. Ryu is this rotation’s sure thing, but he’s on the injured list with a right glute strain, which is considered minor, but further highlights how the Blue Jays are one injury away from being in a far worse spot.

For Matz, a realistic middle ground could be found in his 2018 and ‘19 seasons. Topping 150 innings in each of those seasons with the Mets, Matz pitched to a 4.09 ERA over 62 games (60 starts) in that span. That’s not the solution to the No. 2 job behind Ryu, but it would be a valuable way to solidify one of the back-end spots in Toronto's rotation, as long as he's consistent. That’s what the Blue Jays had hoped to get from Tanner Roark, who was designated for assignment on Friday following a rough 2020 season and a tough start to '21.

“I still feel good about my stuff. What got me this outing is similar to what got me last outing,” Matz said. “You look back at those two changeups, they were on the fat part of the plate, and that’s what got me tonight. As far as my stuff, I’m still feeling pretty good about where that’s at. It’s just small adjustments, and I wasn’t able to make those today.”

The key now, Matz said, is to not overreact. Just because his results have swung, that doesn’t mean he needs to swing, too. He’ll huddle up with Walker to look at how his changeup can be improved, and for a pitcher with Matz’s impressive raw talent, a turnaround can always be one pitch or adjustment away. New challenges will come after later starts, but staying one step ahead of that adjustment game is the key to success as a Major League starter.

Toronto’s offense had a burst, but it fell quiet late, not generating enough runs behind another strong bullpen effort. In the third, Cavan Biggio, Bo Bichette, Vladimir Guerrero Jr. and Teoscar Hernández singled on four consecutive pitches from A's starter Frankie Montas, and none of them were cheap. Guerrero finished with three hits, including a double, raising his average to .356 and his OPS to 1.140.

This showed how impressive this lineup can be when it’s aggressive. George Springer was out for a scheduled rest day and will be evaluated for his fitness to play at designated hitter on Tuesday as he works back to 100 percent from a right quad injury, but Toronto's lineup is quickly finding its stride. The Blue Jays may need that production, too, as Matz and some others who started April hot have cooled off a bit in early May.