In 34 games, he has a 3.34 ERA, 44 strikeouts and 23 walks in 56 2/3 innings. Opponents have batted .267 against Papelbon, a 19th-round Cubs draft pick in 2006.
But more impressive is Papelbon's streak of not allowing an earned run in 21 2/3 consecutive innings over his last 13 outings combined. He put the finishing touches on a masterful month of July by tossing two scoreless innings on Thursday against the Vero Beach Rays, tying a season-high four strikeouts.
Papelbon entered that game in the seventh inning and inherited runners at first and second with no one out. He proceeded to pitch the Cubs out of a jam, inducing a force out at third base and then notching back-to-back strikeouts to close the inning.
It was the type of game in which manager Jody Davis loves to use Papelbon.
"Hopefully we can get him in there when we're in the lead like (Thursday)," Davis said afterward. "He came in (during) a big situation when the game was kind of teetering there and got out of (Adam) Harben's jam … and that's what we like about him."
Papelbon went through a rough stretch of games earlier this season in May, but has rebounded nicely. He says he considers himself a pivotal part in the Cubs' chain of relievers in their minor league system.
"Absolutely," the 25-year-old southpaw says. "I've felt comfortable going out there in relief and trying to bridge (the gap) to the ninth inning, even getting a few saves. I've been trying to keep my team in a situation where we can win the ballgame."
Papelbon's efforts have particularly been on display during this current streak, in which he has had outings of two innings or more six times.
A former starter in college at the University of North Florida in nearby Jacksonville that also started games in the second half of last season at Class-A Peoria, Papelbon has shown the durability to provide his team with more than just one inning in relief on a given night. And because most of his appearances extend past one inning of work, Papelbon has typically averaged one outing over three to four days this season.
One key to his surprising second-half success, Papelbon said, is pitching inside to hitters more frequently. He has also tinkered with his breaking pitch – a slider.
"I kind of moved the ball around to get a little tighter break, just really mixing up my pitches well inside and outside for strikes," Papelbon said of the pitch.
On pitching inside, he said: "I started off the season well because I was hitting outside corners well. But once the season started progressing, I started giving up a lot of singles the other way and wasn't really pitching inside. Rosie (David Rosario), our pitching coach, and even (Daytona hitting coach) Richie Zisk talked about pitching inside more often, and I just started establishing myself more. It's really helped me out a lot."
Even when he's not pitching, Papelbon doesn't venture far from the game. He works with area youngsters as part of a kids camp put on by the Daytona Cubs.
"It's a kid's camp that goes on at the field three or four days," Papelbon said. "I come out to help the kids and show them a few things, and try to have some fun."
The kids in turn have fun with Papelbon, especially once they make the connection between him and his older brother, an All-Star closer.
"They get really excited and it's fine," said Jeremy Papelbon, who has a twin brother, Josh, also in the Red Sox system. "You just play with it and joke around with them. You get a lot of autograph requests."
While Papelbon wants to be his own pitcher, he says he doesn't feel as if he's living in the shadow of his older brother.
"I'm not really upset or whatever, I'm very happy for him," said Papelbon. "I'm glad I have a brother that's made it. It just makes it easier for me to pick someone's brain up there because I'm obviously close with him. It's nice to see what's up at that higher level and to work hard and be that guy. He's where I want to be."
For now Papelbon would settle for a promotion to Double-A. But he noted that a successful season does not have to involve a call-up.
His numbers a season ago at Peoria (9-6, 3.11 ERA in 107 innings) were impressive enough to earn a promotion to Daytona, though he remained in the Midwest League for the duration of 2007.
"Next year, if I can start off and have a good Spring Training and carry it over with a good month, maybe the next thing you know I'll be in Chicago," Papelbon said.
The Cubs' front office thinks it could happen.
"He's a left-hander who throws strikes, competes and has a big heart," said Cubs Vice President of Player Personnel Oneri Fleita. "You can't ever rule him out."
InsideTheIvy.com staff writer Corey Ann Dobridnia in Daytona Beach contributed to this report.