Casting a shadow over Friday’s thrilling 5-4 walk-off win over the Orioles was a potentially major loss for the Blue Jays, as reliever Jordan Romano was forced to leave the game with a right middle finger injury.

Romano, who surrendered the game-tying home run to Renato Núñez in the eighth inning, was evidently feeling some discomfort in that finger as manager Charlie Montoyo and the Blue Jays’ trainer spoke with him on the mound of Sahlen Field. He is now undergoing tests, with an update expected over the weekend.

“It wasn’t a blister,” Montoyo clarified after the game. “It was a right middle finger injury.”

It’s difficult to overstate the value of Romano, who has been the story of the season for this Blue Jays bullpen. The Canadian right-hander has fully realized his potential thanks to an improved approach, carrying a 1.23 ERA with a fastball that’s averaged 96.5 mph. His slider has been nearly unhittable, too, after he dropped his changeup and focused on the two-pitch mix.

There is no sense at this time of how serious the injury is, but Romano’s role in the Blue Jays bullpen has been critical in the absence of Ken Giles, who is progressing towards throwing his first live BP session as he works his way back from a right forearm strain. Romano has been trusted by Montoyo with high-leverage spots, including save opportunities, alongside Anthony Bass.

If Romano is forced to miss time, expect to see more of fellow right-hander A.J. Cole, who has been a strong option behind Romano and Bass, along with Rafael Dolis, who picked up the win on Friday.