(John Bazemore / AP)

The notion of chemistry in team sports is vague and clichéd, but Davey Johnson has developed a view that comes with a tangible definition. “Chemistry is when everybody is in a role where they know their role, and they’re prepared to do their role mentally and they do their role,” Johnson said. “And if they do it well, they know that it will be expanded.”

For Johnson, the Nationals’ chemistry has been off this season, and he believes it ties directly to the makeup of the bench. Johnson desires veteran reserves, players who have handled the role before and feel comfortable about their status in the majors. In Tyler Moore, Steve Lombardozzi, Chris Marrero and Jeff Kobernus, Johnson has managed bench players hungry to establish themselves and perhaps uncertain about their place.

When you hear players and Johnson talking about the lack of an “identity” or not playing “loose,” this is what those buzzwords really mean.

“When the sum of the parts don’t perfectly fit because young players feel an urgency to establish themselves up here and in a job they’re not used to doing,” Johnson said. “They’re used to playing every day. When you play on a team that’s got everyday players and you don’t get to play but maybe once or twice a week, there’s going to be, not everybody can welcome the role as a challenge. It’s more of an audition.

“It has a different feel to the ball club. There’s not the relaxation that you would expect when you have some veterans situated around you and they’re not concerned about their contract for the next year or whatever. They know they’ve been successful at this level and they’ll be playing baseball next year probably in the same role. Younger guys feel like this is my chance to establish that, ‘I’m a big leaguer.’ And then when you throw them in a different role, it’s just hard. It’s very hard. So that’s the mood.”

Johnson feels the Nationals’ bench is improving, but it has obviously slacked compared to last year, despite largely the same makeup. Playing time has been less frequent. Moore struggled so much the Nationals sent him to Class AAA for more at-bats. Johnson placed the blame on himself.

“My job is to be able to put everybody in a situation where they succeed, and I know it’s going to be very difficult for them to be able to succeed so, I’m having a bad year,” Johnson said. “I’m not doing my job properly. I’m not getting these guys in roles that they’re comfortable with.”

As he discussed his bench and the reason why veterans make better reserves than young players, he also hinted he may push for the addition of a right-handed bat, the role Moore would have filled before inconsistent playing time sunk his second major league season. Marrero has been given the chance at that spot now, but Johnson didn’t rule out Moore coming back.

“He’ll probably be in the mix pretty soon,” Johnson said. “He fits more of a right-handed bat that can come off the bench and drive in a run. We’re not right where we need to be, but we’re getting there.”

If the Nationals decide to wade into the trade market for a veteran, right-handed hitter, they would find no shortage of options, with varying degrees of impact. Scott Hairston of the Cubs, Josh Willingham of the Twins and Aramis Ramirez of the Brewers come to mind as three right-handed bats whose teams figure to be out of contention. There’s also this Morse guy from Seattle who, we hear, has been helped out a team’s chemistry before.