"They've definitely helped us out in a big way," Napoli said of the two big right-handers. "They kind of struggled a little bit early, but they grew, figured some things out. Most of it is confidence. They've got the stuff."
Napoli means real confidence, not bravado. For relief pitchers, this comes only with success under duress.
In Bulger's case, the major breakthrough came when he notched his first save after Fuentes faltered in a July 28 save situation against the Indians.
Clinging to a two-run lead, Fuentes left the bases loaded with no outs in the top of the ninth for Bulger. Bringing his mid-90s mph heat with a sharp breaking pitch, he induced a brilliant 3-6-1 double-play grounder from Victor Martinez.
When Jhonny Peralta grounded out to end it, Bulger's first big league save -- at age 30, after a long struggle -- was a memorable one.
"That was huge for Bulg," said Napoli, who was calling the pitches. "That kind of put him over the top. He has a kind of quiet swagger now, and I like that.
"I think he knew he could be a good pitcher here, but that showed him what he could do. It gave him the confidence to be that person he thought he could be, that he could pitch in that situation and do something like that."
Jepsen, like Bulger, had been building toward his big moment with a succession of solid outings.
Jepsen's major breakthrough came on Saturday against Texas. Entering in the top of the eighth with runners on second and third and one out, Jered Weaver's decision hanging in the balance, Jepsen shut down the Rangers.
First he struck out Michael Young on a 3-2 fastball that hit 97 mph on the radar gun "and exploded," as Napoli put it. Napoli was in the clubhouse video room at the time, watching Mathis call all four-seam and cut fastballs for Jepsen against Young and Marlon Byrd.
Byrd sent another 97-mph heater to right to end the threat, and Jepsen came back out to strike out Andruw Jones with more heat before Fuentes closed the show.
"Jeppy's probably our hardest thrower," Napoli said. "He was dealing 97 consistently [on Saturday] and painting with it, hitting corners. If you put it over the plate against Young, he's going to hit it in that situation. Jep just blew it by him. That was impressive.
"That was big for Jep, and it was big for us. We needed it."
Bulger has a 2.16 ERA in 37 games, covering 41 2/3 innings, since April, when 10 earned runs in 7 2/3 innings bloated his ERA. Left-handers are batting only .188 against him, and his .202 overall batting average against is the best on the staff.
Jepsen owns a 2.25 ERA in 16 innings since July 1. His ERA is also inflated -- it's 6.51 overall -- by a bad start complicated by back issues that sent him to the disabled list.
Bulger and Jepsen are healthy and dealing now, and the manager, Mike Scioscia, likes what he sees.
"We're going to need both those guys," Scioscia said. "Right now, we've got a good foundation with Bulger and Jepsen and Darren Oliver, if it's a matchup situation, getting to Fuentes. It could be who's fresher, a matchup situation. It's good to have a couple of guys throwing the ball with the ability to get a strikeout late in games.
"Bulger's last 20, 25 appearances are off the charts. And Jepsen, the last 10 to 15 innings, has been as good as any reliever in the game."