Jonathan Papelbon yelled from his locker to Washington Nationals clubhouse attendant Mike Wallace in the middle of the room. The message: tell Gio Gonzalez to get on the stationary bike.

Out on the practice fields in Viera, Florida, Papelbon stopped a drill because Gonzalez wasn't doing it right, something new manager Dusty Baker said was ''a sign to me of a good team.''

The Nationals hope to become a good team again, but it wasn't clear if Papelbon would be a part of the club six months after a dugout altercation with teammate and National League MVP Bryce Harper. Papelbon apologized to Harper and the organization, and general manager Mike Rizzo expressed no hesitation in bringing him back because of the due diligence the front office did before acquiring the 35-year-old closer at last season's trade deadline.

''We talked to his teammates in Boston and in Philly, and players who knew him around the league and found no teammate that has a bad thing to say about him,'' Rizzo said.

Papelbon the closer is undeniable, converting on 24 of 26 save opportunities last season and 349 of 395 throughout his major league career, which includes a World Series title with the Boston Red Sox. Papelbon the teammate is a more complicated character - a mix of intense competitiveness, light-hearted ribbing, loud country music and a Southern twang.

''One incident doesn't define who you are as a human,'' said Nationals pitcher Bronson Arroyo, who played with Papelbon for parts of three seasons with Boston. ''I think that inside this locker room, by the time (the season gets) going here, I don't think there'll be any kind of issues from him. He's a solid guy, and I think anybody would take him on their team.''

The image of Papelbon putting his hands on Harper's neck during a game Sept. 27 may follow him for some time. He received some boos the first time he stepped on the mound at Space Coast Stadium for a Nationals spring training game, but Rizzo said fans have to trust him that Papelbon will help the team win.

Harper said when he arrived at camp that he had moved on, and that Papelbon was contrite in his apology.

''I'm an imperfect person living in an imperfect world,'' Papelbon said. ''My whole point is that good can come of this. I can redirect this, and we can go out and win 95 games this season and go into the playoffs and be hot and go win a world championship still.''

Inside the Nationals' clubhouse, that belief exists. With a rotation headlined by Max Scherzer and Stephen Strasburg and a lineup featuring Harper, Washington is again a contender after missing the playoffs last season.

Rizzo traded former closer Drew Storen to the Toronto Blue Jays for outfielder Ben Revere, ensuring Papelbon will be a big part of the Nationals' resurgence, keeping the closer job he wanted when he waived his no-trade clause in July.

Being a leader is something several former teammates say Papelbon is, even if he marches to his own beat.

''I think people didn't see him, like the real Papelbon,'' Phillies reliever Luis Garcia said. ''I really saw that he was different. For us in the bullpen, he was great with us, talking with us about stuff.''

Even though Papelbon's brash attitude wore thin on a losing team in Philadelphia, teammates respected him for getting his job done on the mound.

''If anybody gets in front of a microphone and tries to tell you that they don't have any problems, they don't have any issues, they don't rub people the wrong way ever, then they're going to be liars,'' Phillies outfielder Cody Asche said. ''Maybe he's done it on a bigger scale than others have, so it's a little bit more magnified.''

Papelbon was a mentor of sorts to hard-throwing reliever Ken Giles, whom the Phillies traded to the Houston Astros in the offseason. Giles said getting to know Papelbon makes someone's opinion about him ''do a full 180.''

''A lot of people forget that he won a World Series, he knows what he's talking about, he's been there,'' Giles said. ''He's just trying to tell everybody that hasn't been there what it's like and he makes sure to show them what it feels like to be that successful and win a World Series.''

The Detroit Tigers' Jarrod Saltalamacchia, who caught Papelbon in Boston, said Papelbon is far different as a person than people perceive from the outside.

''We judge people for what we see instead of getting to know somebody,'' Saltalamacchia said. ''I know playing against him I loved him just because I love the way he came in, was serious as could be, had one job and did it. As a player you just get to love him more as a person and see he cares, he's a good dude.''