Riding a five-game losing streak in which they were outclassed, not just outscored, the Blue Jays needed their ace on Saturday night at Citizens Bank Park. Hyun Jin Ryu showed up and did his job against the Phillies, but even that wasn’t enough as the Blue Jays dropped their sixth in a row.  

Ryu has been the great stabilizer for the Blue Jays this season as they’ve dealt with injuries, particularly to their rotation, but only a shutout would have done in the 3-1 loss. A pair of tough outings in early September left Ryu searching for better in-game adjustments, which he’s now nailing just in time for the approaching playoffs.

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“He’s an ace. He gave us a chance,” said manager Charlie Montoyo after the loss. “Everybody felt good going into the game and he did what he was supposed to do. He kept us in the game, and he gave us a chance.”

By failing to capitalize on that chance, the Blue Jays have now been outscored 61-23 during this six-game losing streak and have fallen back to .500 for the first time since Aug. 25. Toronto still has some breathing room on the Tigers and Mariners for the eighth and final American League playoff spot, but they’ll need to reverse the trend regardless of their playoff odds. Step one might be as simple as following the lead of Ryu, who entered Saturday with an adjusted game plan that worked as intended.

Instead of working off his fastball, Ryu threw more cutters (36) than any other pitch on Saturday. That set up a sharp curveball for him, especially early, but when Ryu is at his best, there aren’t many pitchers in baseball who can rival his changeup.

“The cutter and curve, you can throw them for a strike but you can also expand with them in any given count,” Ryu said through an interpreter, “so I was able to get a lot of swings and misses and also get some soft contact, which is crucial for my outing. Executing my curveball and cutter worked out really well.”

Of the 26 changeups that Ryu threw over his six innings of work, his finest was saved for the final strike of the third against Phillies star Bryce Harper. With a 2-2 count, Ryu threw Harper a changeup low and inside that kissed the bottom edge of the zone as Harper swung well over the top. It was either “How?” or “Wow” that the broadcast cameras caught Harper saying as he dropped his helmet and stared back to the mound, undoing his batting gloves -- but either way, the veteran left-hander earned it.

Lefties don’t often turn to their changeup in a two-strike count facing a left-handed hitter, but Ryu doesn’t always subscribe to that thinking. The element of surprise might not hurt, either.

“That was the first changeup that I showed Bryce Harper in that at-bat. It was really crucial to execute it well,” Ryu said. “The angle of it was particularly nice, so the changeup went in the way that I wanted with two strikes. In general, I don’t think I need to shy away from a changeup just because I’m facing a lefty. I think it’s better if you can execute all types of pitches in any given count so it adds more options. That’s how I look at it.”

The Phillies eventually got to Ryu in the fifth on a Jay Bruce double that was followed by a string of three consecutive ground ball singles -- so while he walked off the mound after six with the Blue Jays trailing, he still hadn’t allowed much hard contact. Ryu’s ERA now sits at an even 3.00, a number that he’s mostly outperformed, and the Blue Jays will need him to pitch to the peak of his abilities come playoff time.

There may not be many pitchers in baseball more valuable to their team than Ryu this October. Yes, other clubs have aces, but many contenders have three or more starting pitchers who they can be confident in to go deep in a big game. Between injuries and inconsistencies, Ryu is pulling the weight of the entire rotation for the Blue Jays and his starts will be must-win games, given the uncertainty behind him. It’s always unwise to bet against the crafty lefty, though, and he has 40 innings of postseason experience from his Dodgers days to lean on this October.