SAN FRANCISCO -- Gabe Kapler was in a tough spot Sunday morning. At the end of a six-game road trip, Kapler entered the game knowing that some of his best relievers desperately needed a day off.
The Giants already are without closer Jake McGee because of an oblique strain, and for the finale against the Colorado Rockies, Kapler preferred to stay away from Tyler Rogers, Tony Watson and Dominic Leone, his three primary setup men.
That left the final six outs Sunday to Camilo Doval and Kervin Castro, which ended up being pretty fortuitous for the Giants. It gave them a glimpse at the potential future back end of this bullpen, and also one more piece of evidence that both young right-handers fully belong on a postseason roster.
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Those decisions will be made over the next week-plus, but at the moment it's hard to imagine either being left off, even though neither was on the roster when this month started. Doval was recalled from Triple-A for the fourth time on Sept. 5 and two days later Castro made his big league debut. All they have done since is throw 20 2/3 shutout innings, with just 14 hits allowed to 22 strikeouts.
"Oh man, they've been unbelievable," right-hander Kevin Gausman said. "You can just kind of see the confidence ... they both might be on the (playoff) roster and they both deserve it."
The results have been overwhelming and the stuff is certainly impressive, with Doval hitting 102.5 mph earlier on the trip and Castro showing an uncanny ability to land his curveball for strikes at Coors Field, where breaking balls generally go to die. But what has really put both in position to pitch in October is the poise they have shown in huge spots.
Doval entered with the bases loaded and no outs in the middle of last Wednesday's win at Petco Park and threw three straight nasty sliders to strike out Manny Machado, who crushed nearly everything the Giants threw at him for three days. He then got Tommy Pham to hit into a double play.
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Castro was called on in close games Thursday and Friday and struck out five of the 11 batters he faced. The next day, he told Kapler he was game to pitch again despite having taken on a heavy workload.
Kapler turned to the rookies Sunday, with Doval getting the eighth in a tie game. The 24-year-old struck out the side while facing the heart of the Rockies' order, getting swinging strikes on six of the 17 pitches he threw.
It wasn't a save situation when Castro entered in the ninth, but at Coors Field, a four-run lead might as well qualify. The 22-year-old gave up a leadoff single but then induced a double play from C.J. Cron, Colorado's most dangerous hitter. He threw a 95 mph fastball past Sam Hilliard to end the game and clinch a sweep.
"They're both definitely poised in different ways," Kapler said. "Camilo is so calm and he just wears that this is not stressful for him. He wants to perform but it's not overwhelming to him in any way. In Castro, I think it comes in the form of intensity. It's just focus and a channeling of adrenaline. I think they've both shown a ton of poise."
The two will always be connected because they're young, hard-throwing righties who were added to the 40-man roster at the same time. But Doval is so calm that assistant pitching coach J.P. Martinez jokingly checked his pulse after the escape job in San Diego. Castro has only been here a few weeks but already might lead the bullpen in fist pumps. Gausman described him as "a bulldog."
Kapler noted the differences but said what he has seen from both is that they seem to get better each time they take the mound.
"Both of those guys, as they've pitched more, have gotten sharper and a feel for their pitches," Kapler said. "Now it's a bit of a double-edged sword. You want to keep getting them out there and have them understand themselves better, but you also don't want to burn them out. I think the really good thing is both of them are just young and probably have very little wear on their tires relative to a lot of relievers around the game."
That's a huge plus as the Giants head to October. Their two hottest relievers right now are young and eager to get tested in big spots. The Giants had a feeling both could handle it, but during a month when every game has been monumental, Doval and Castro have shown the staff that they can be trusted when the game or a series is on the line.
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Kapler said evaluating the rookies was important this month, but added that the process didn't start in September. He has had a close eye on Castro since the instructional league last fall in Arizona and Doval has looked like a potentially important bullpen piece since a breakout spring.
"To be honest the evaluation of those two guys has been going on for a really, really long time," he said. "We've talked about those guys a lot and when the right time was and how much experience they would need to be good for us in this time of year, and I think they're both in a place where there's no trepidation about putting them in big spots, which is nice."