SAN FRANCISCO -- If the Giants wanted to give their fans a real thrill over the final 20 games of the regular season, something to whet their appetites for 2023, they could take a bold step and give top pitching prospect Kyle Harrison a callup for a game or two to see how those 180 strikeouts in 108 Minor League innings this season would translate in the Majors.

The Giants have myriad reasons to resist that urge; the club doesn't need to add the 21-year-old lefty to the 40-man roster this winter to shield him from the Rule 5 Draft. They need all the spots they can preserve for the prospects they do need to protect.

When asked before Tuesday night’s 5-1 loss to the Braves about the possibility of a Harrison callup, manager Gabe Kapler did not respond with a flat “no.”

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“I don’t want to say that there’s no chance,” Kapler said, “but our discussions have been limited around that topic.”

Tryouts for 2023 will remain on the forefront, with or without that unlikely pie-in-the-sky cameo from Harrison, at least for pitchers. This is the time to do it. The Giants not only are out of contention, but after Atlanta leaves town Wednesday the Giants might not play another game that impacts any playoff race, depending on where the Padres stand in the season’s final series.

To that end, rookie Sean Hjelle, who threw five excellent innings in Milwaukee on Thursday, is expected to start Saturday against the Dodgers, or be the bulk-innings guy after an opener, because Alex Wood is not ready to return from a shoulder injury. The 6-foot-11 right-hander could be part of the 2023 rotation.

The bullpen might gain 24-year-old right-hander Cole Waites, the club's No. 29 prospect. He rocketed this season from High-A Eugene to Triple-A Sacramento, where he allowed three hits in seven shutout innings over six appearances.

On Tuesday night, with the Giants down three runs in the seventh inning, Waites had a memorable Major League debut.

After walking Ehire Adrianza on four pitches and allowing a Ronald Acuña Jr. double to put two runners in scoring position with nobody out, Waites escaped by retiring three big hitters. He retired Dansby Swanson (who already had a two-run homer) and Austin Riley on grounders to a drawn-in infield, then Matt Olson on a fly ball.

When Waites returned to the dugout, Evan Longoria and pitching coach Andrew Bailey took turns tapping the rookie’s chest to make sure his heartbeat hadn’t hit 150.

The kicker: Waites grew up 45 minutes from Atlanta as a diehard Braves fan. He might have made his big league debut in Chicago over the weekend after he was flown in for the taxi squad, with his mom, dad, brother and girlfriend flying up, too, but he was not activated and had a more meaningful debut against the Braves.

“I think this is the way it was supposed to happen. That’s for sure,” Waites said. “We waited around in Chicago, but I think this was supposed to be the team to throw against.”

Jakob Junis, who started for the Giants and took the loss, is not in the same tryout situation for 2023. He has plenty of Major League experience. The question is where Junis might fit next year. For now, he is struggling to maintain the consistency that made him one of the team’s best starters in May before a hamstring injury landed him on the IL in June. Junis’ pitching has been a “mixed bag” since, as Kapler said.

Asked what Junis has shown in his first season in San Francisco, Kapler said, “I think he proved that we evaluated him correctly, which is a quality Major League starter.”

Junis allowed four runs in five-plus innings, one scoring in the third after right fielder Luis González lost a two-out Travis d’Arnaud liner in the lights, a gift double that turned into a run on a Michael Harris II single.

That was after Junis made his worst mistake, a hanging slider that Swanson hammered over the left-field wall earlier that inning to break 1-1 tie.

“That was really the main difference in the game,” Kapler said.