CHICAGO (AP) -- Tanner Roark made a successful return to Washington's rotation on Monday. It was like he never left.
Roark pitched five effective innings, Wilson Ramos hit a tiebreaking homer and the Nationals beat the Cubs 2-1 in the first major league matchup of young sluggers Bryce Harper and Chicago rookie Kris Bryant.
Denard Span also homered for NL East-leading Washington, which has won eight of nine.
Making his first start of the season in place of the injured Doug Fister, Roark (1-2) allowed Bryant's sixth home run and struck out three. Four relievers combined for four innings of two-hit ball, with Drew Storen working the ninth for his NL-best 15th save in 16 attempts -- closing out the five-hitter.
"With the exception of one slider to Bryant, (Roark) threw the ball exactly where he wanted to throw it today," Washington manager Matt Williams said. "He really kept his pitch count down through five.
"He knows how to pitch. He knows how to get guys out."
Roark won 15 games last season, but was shifted to the bullpen when Washington signed free agent Max Scherzer. The Wilmington, Illinois native had a large contingent of friends and family in the stands.
"Coming off the mound each time, each inning, I could definitely hear some people with recognizable voices that were in the crowd," said Roark, who also played his college ball at Illinois.
Roark also got some help from his defense. Left fielder Michael Taylor made a diving catch of Tsuyoshi Wada's liner to left to end the second inning with Chris Coghlan on first.
"I threw my hands up in the air," Roark said. "That was a heck of a catch."
Then Harper made a leaping catch at the wall on Anthony Rizzo's fly to right with two outs and Bryant on first in the third.
"(Harper) made a nice play running full stream into the wall," Williams said. "He catches it with the left hand and braces with the right.
"It got the forearm and elbow, but he's OK."
Wada allowed one run and four hits in 5 1/3 innings in his second start since being recalled from Triple-A Iowa. Justin Grimm (1-1) relieved Wada and yielded Ramos' two-out drive to right in the sixth.
"Both sides pitched really well," Chicago manager Joe Maddon said. "I'll take our performance and also my takeaway is that's as good as anybody we played so far.
"We lost 2-1 . but give them some credit regarding the defense they played in the outfield. Those were the game changers."
Bryant went deep in the first and also had an infield single. He reached in the ninth when a replay review showed he was hit by a pitch, but Storen retired the next three batters.
Harper went 1 for 3 with a double and a walk.
The 22-year-old Harper and 23-year-old Bryant are from Las Vegas and faced each other in games as late as high school.
"We grew up playing against each other, playing with each other and now it's a bigger stage and obviously that's pretty cool to do, living out our dreams," Bryant said before the game. "It's something we always wanted to do."
Leading off the game, Span smashed a 2-2 pitch off Wrigley Field's new scoreboard in right. But Bryant connected in the bottom half, lining a 1-0 pitch into the first row of bleachers in left.
Nationals: OF Jayson Werth (bruised left wrist) will rejoin the team in Chicago on Tuesday but isn't expected to play. "We'll see where he's at as far as swinging the bat," Williams said. "If he's ready to do that then we'll get improvement and get him going." ... Fister, on the DL since May 15 with right forearm tightness, is expected to start throwing later this week, according to Williams.
Nationals RHP Jordan Zimmerman (4-2, 3.52 ERA) faces RHP Kyle Hendricks (1-1, 4.14 ERA) on Tuesday night. Hendricks pitched his first career shutout in his last outing on Thursday in San Diego. Zimmerman is 0-3 in three career appearances in Wrigley Field and has not pitched there in two seasons.
The even-tempered Bryant and often-brash Harper exchanged compliments in separate pregame chats with the media.
"When we were younger, we use to call (Bryant) `silk,'" Harper said. "He was so smooth with everything he did."
"I think we have very different personalities," Bryant said. "It's good to have guys who wear their heart on the sleeve and he's one of those guys. It's awesome to see that. He plays so hard for his team."
Although Bryant said he hasn't stayed in close contact with Harper, he said he hoped to reach out to the slugger in the offseason so the two might "play some golf, hang out and work out."