CHICAGO -- With all this talk of run differential, you would think some of the Chicago Cubs sluggers would be putting up some huge numbers, but guess who’s second on the team in RBIs after driving in four in a 5-2 victory over the Washington Nationals on Thursday?

It’s not Jason Heyward, who returned mid-game when Dexter Fowler got ejected. And it’s not Fowler, who has hit everything in sight. Kris Bryant is the easy answer, of course, but he, too, lags behind 34-year-old Ben Zobrist after Zobrist drove in the winning run for the second straight day. He also went deep on consecutive days as he’s starting to heat up.

“It’s a good sign,” Zobrist said after the game. “It takes me a while sometimes to get the feel. I’ve definitely felt better the last couple days driving a couple balls. Sometimes driving it takes a while. See if we can continue that the rest of the weekend.”

Zobrist thought about signing with these Nationals in the offseason, and considered the New York Mets, too, but his heart was always in his native state. So when the Cubs made the right offer -- four years, $56 million -- he jumped at the chance to join his former manager. The Mets and Nationals aren’t bad right now, but they’re not the Cubs, who improved to 21-6 thanks in large part to Zobrist at the plate.

Ben Zobrist is second on the Cubs with 20 RBIs after driving in four in Thursday's win over Washington. David Banks/Getty Images

“Offensively it was Zo’s night,” Chicago skipper Joe Maddon said. “He was fabulous.”

His 20 RBIs -- half coming in the past four games -- are second among Cubs only to Anthony Rizzo. Zobrist sliced a single to right with the bases loaded in the fourth inning to bring home two, then turned around to hit right-handed and smash a two-run shot in the eighth.

“It’s nice to get RBIs and be in that situation a lot,” Zobrist said. “I have to do a better job of coming through.”

That’s the bad news. The Cubs are getting on base for Zobrist so much his batting average doesn’t look very good with men in scoring position -- it’s just .200 after Thursday’s game. He and Rizzo lead the team with 40 at-bats in those situations, but Rizzo is hitting .325, hence his seven more RBIs. Then again, Zobrist wasn’t thought of as a middle-of-the order guy when the Cubs signed him, but Maddon has him hitting third or fifth. The manager forecast that configuration in spring training, but everyone thought Zobrist would end batting higher or lower in the lineup.

“I guess it surprised me a little bit, but I have done that in the past before, too,” Zobrist said. “We’ve been playing well -- that’s probably why he kept it there, but that doesn’t mean it won’t change tomorrow.”

And even though it takes time for Zobrist to find his groove, he still has a lofty on-base percentage of .377. And while that .200 average with men in scoring position doesn’t look pretty, it’s the total number of runs batted in that matters, right? Assuming he plays 150 games, Zobrist is on pace for 111 RBIs. No one will care what that batting average is if he comes anywhere close to that.

“There’s something to be said about getting the ball rolling in the right direction early,” Zobrist said of the team and himself.

Though he flirted with the Mets and Nationals, the Cubs were always where he wanted to be. He noted that it all worked out in the end, with Daniel Murphy off to a good start for Washington and Neil Walker in a similar groove for New York. Zobrist is doing his part for the best team in baseball and finds himself right in the middle of it all.

“Rizz is getting on base and they’re pitching around him to get to me,” he said. “If I get some more hits, he’ll get some better pitches to hit. I’m doing the best I can to protect him.”

Who would have thought Zobrist would be called upon to protect Rizzo? He’s been a much more valuable piece of the Cubs puzzle than perhaps people realize, and from the sound of it, that includes even him. There have been so many contributors already to the Cubs' success; the past couple of days have been Zobrist’s turn, and he’s come through.

“It was another good game tonight all the way around,” Zobrist said. “Right now we’re playing great baseball and we’re doing well.”