GLENDALE, Ariz. -- Aaron Bummer was sitting in an Applebee’s in 2017 when his career path as a pitcher took a major step forward.

The White Sox left-hander actually wasn’t positive of the exact restaurant locale. But he does remember a dinner conversation with Ryan Riga, his teammate with Class A Advanced Winston-Salem at the time, concerning a change of approach with his sinker.

“We were sitting at an Applebee’s or something after a game and watching Zack Britton pitch, and we were like, ‘That thing is disgusting. How are we going to figure that out?’” Bummer said. “We went on You Tube that night, found out how he was gripping it and spent the entire next day during BP playing catch for 45 minutes trying to figure out what he was doing.

“That was kind of, we found something, we found something that worked. We found something that sinks. So, we were like, ‘Here we go.’ It’s something different. It’s not the way most people throw. But it works for me.”

Bummer previously was throwing a different variation of the two-seamer but took his fingers off all the seams when throwing the new and improved sinker. At first usage, Bummer laughed when describing how he got his teeth kicked in.

But that sinker now has become a dominant pitch. Bummer jumped four levels in 2017, ultimately finishing with a 4.50 ERA over 30 games with the White Sox. He posted a 4.26 ERA over 37 games in '18 before becoming an integral late-inning piece in ’19 as shown by his 2.13 ERA, 27 holds and just 43 hits allowed over 67 2/3 innings and 58 games.

According to Statcast, Bummer ranked second behind none other than Britton with a 71.4 percent ground[-]ball rate last season. He also allowed the fifth-lowest expected slugging and was tied for the fourth most vertical movement on sinkers at 6.5 inches more than average, based on other sinkers thrown at similar velocities. It’s a pitch at the core of his five-year, $16 million extension, with two club options, announced on Feb. 22.

“Really, ever since I found it in Winston-Salem in 2017, I haven’t touched it. I haven’t tried to manipulate it,” said Bummer of his sinker. “That’s one of the reasons why I’ve grown to have success with it. I’m trying to throw the ball down in the zone to the best of my ability. At the end of the day, I’m going to live and die with that.”

For some reason, Bummer doesn’t need a seam to be able to feel the baseball on his sinker thrown at an average velocity of 95.8 mph in ’19, per Fangraphs. Jace Fry, another talented left-hander in the White Sox bullpen, has talked with Bummer about his sinker, according to Bummer, but can’t command it without the seams.

“Thankfully it worked out pretty well,” said Bummer, who also features a cutter and occasionally mixes in a four-seamer, changeup and slider. “Hopefully it’s there the rest of my career.”

Manager Rick Renteria recounted a story Saturday of having a talk with Bummer, who was expressing how excited and impressed he was watching Michael Kopech, Dylan Cease and Dane Dunning throwing sides. Renteria quickly let Bummer know he wouldn’t want to sit in the box with Bummer pitching either.

“He can get a lot of ground balls for us in big situations. We are not afraid to use him in any situation,” Renteria said. “This is 95, 96, 97. I mean, with some sinking action. It’s pretty special.”

This journey unofficially began at Applebee’s, by watching Britton in action. Other young hurlers looking for an edge might be studying Bummer’s sinker in the not too distant future, causing Bummer to smile and shake his head in almost disbelief.

“There’s so much information out there,” Bummer said. “You can go watch 'Pitching Ninja' videos and they will show you exactly how certain people are throwing it. You have every opportunity to go out there and figure something out or change a grip or mirror somebody. The information you are able to get now, it’s a blessing. It really is, to go out there and figure things out that way.

“It’s just being able to find command with it and being comfortable with changing the grip and changing something. You just kind of look at yourself and say what you want, are you willing to take the lumps and bruises that changing something might take.”