CHICAGO -- Ian Happ started in left field on Thursday, and he has now played all three outfield positions and handled them well. The question the Cubs need to decide is what to do with the rookie when Jason Heyward is ready to come off the disabled list.
Heyward, who has been sidelined with a sprained right index finger, made his first rehab start on Thursday with Class A South Bend and went 1-for-3 with an RBI single in the sixth. Heyward, who started in right field, is eligible to come off the DL as soon as he's ready. Happ has made quite an impression since he was called up on Saturday, hitting a pair of home runs in his first three games. He's 6-for-17 in five games so far with two doubles, two homers and four RBIs.
"I'm just staying in the present moment and taking it one day at a time," Happ said after Thursday's game in which he was 2-for-4 with a double. "Today was fun, we got the sweep [against the Reds], and I'll come back tomorrow and play baseball."
Cubs manager Joe Maddon did not indicate the team's roster move, except to say he likes having eight relievers, which would mean a position player would need to go to make room for Heyward on the 25-man roster.
"There's no reason [Heyward] has to be back [Friday]," Maddon said. "I said, 'You let us know what you think.' Ian is looking like he does not want to go anywhere."
Happ, who is ranked the club's No. 2 prospect by MLBPipeline.com, played second base most of Spring Training, but reports from the Cubs' Minor League coaching staff, including outfield coordinator Doug Dascenzo, convinced Maddon that Happ can play the outfield. Happ has reinforced those reports by what he's done, beginning in St. Louis over the weekend.
"He's very athletic, more than I'd been led to believe," Maddon said. "I thought he was more offensive oriented."
What's also impressive is how easily Happ has transitioned from the Minor Leagues to the big leagues, similar to how Kyle Schwarber, Kristopher Bryant and Addison Russell handled the move. They were not intimidated at all.
"I find myself using the word 'calm' a lot," Maddon said. "When they get here, they're not affected. I don't know exactly why, I don't even know if that speaks to where they come from amateur-wise or the kind of attention they got prior to getting here. They're just different in their ability to handle this rather quickly."
Worth noting
• The Cubs added reliever Pierce Johnson prior to Wednesday's game, giving them eight relievers.
"I just think this number bullpen-wise is right," Maddon said. "It's nice to have the extra guy on the bench, don't get me wrong. Game in progress, there's so many other things to do. We just haven't decided yet. I like the extra reliever. I also like the extra bench player. I'm really going to campaign for the 26th man on the roster. I think it would be a perfect number."
Johnson was 2-0 with a 3.21 ERA in 12 outings with Triple-A Iowa this season, striking out 21 batters over 14 innings. He was the first pitcher selected in the Draft by the Cubs when Theo Epstein took over as president of baseball operations. He had been primarily a starter, but he has made the transition to the bullpen.
"This is a role I really enjoy, and hopefully I can have more success in that," said Johnson, who talked to Wade Davis and Mike Montgomery for advice.
It's a little simpler being a reliever.
"This way I can go out there and give it my all, instead of as a starter establishing the fastball, mixing in the breaking ball and having a plan of attack," Johnson said Thursday. "Now, it's my best versus their best, and that's translated into success for me."
Johnson was in the bullpen on Wednesday, and he was a little nervous.
"Yesterday I was sitting there and every time the phone rang, my heart started beating a little faster," Johnson said. "It's been a fun 24 hours."
• The Cubs commemorated the 70th anniversary of Jackie Robinson playing his first game at Wrigley Field by raising a No. 42 flag on the right-field foul pole. Wrigley is the only remaining Major League ballpark in which Robinson played. The game, played May 18, 1947, drew a paid crowd of 46,572 fans, the largest paid regular-season crowd in ballpark history.

Jackie Robinson's granddaughter, Meta Robinson, helped raise a new flag to honor his legacy.
The Cubs had previously flown a "JR 42" flag on Wrigley Field's roof following the retirement of Robinson's No. 42 by Major League Baseball in 1997.

• Since Johnson was with Happ at Iowa, what's his scouting report on the rookie?
"He's seeing beach balls," Johnson said. "Seeing him in Triple-A, it was awesome. He was hitting bombs left side, right side, hitting them opposite field. He's just hitting the ball hard, too, and that was something that stuck out to me."