Brady Singer began his third Major League start by striking out Cubs leadoff man Kris Bryant on a slider that darted wickedly out of the strike zone. His finish in the fifth inning was equally impressive: a 92 mph heater that Javier Báez chased up in the strike zone and missed.

In between, there were flashes of all the Royals hope to see from their No. 3-ranked prospect. But on Singer’s 24th birthday Tuesday night at Wrigley Field, a 5-4 loss to the Cubs served as a reminder of the thin line separating success and failure in the big leagues.

He only made a couple of mistakes, but the Cubs homered on both of them. One was a slider Jason Heyward drilled over the right-field wall for two runs in the bottom of the second inning.

Jason Kipnis got the other one on a fastball that caught too much of the plate in the bottom of the fourth and resulted in another long, towering two-run home run. With Singer throwing 93 pitches in five innings, the long balls were enough to beat him as Cubs ace Kyle Hendricks was his usual efficient self, allowing two earned runs in seven innings for his second victory of the season.

Hendricks had his way with a Royals offense that began the day having not scored in 13 innings. That streak was snapped at 14 when three straight Royals reached base to open the second inning.

But the Royals made a game of it in the ninth inning, scoring twice, both off reliever Craig Kimbrel, and stranding the tying run at third when lefty Kyle Ryan got Bubba Starling on a hard grounder to Bryant for the third out.