MIAMI -- Starlin Castro grew up idolizing Hanley Ramirez, and now he gets to compete against him.

The 21-year-old had a strong showing last night in front of one of his favorite players growing up, picking up two hits in a 7-5 Cubs win.

"It's great to play against him," Castro said. "He's a great player and a great guy. Just a few years ago, I would watch him on television, and these past two years, it has been great to play against him."

Castro, who was batting .329 entering Thursday, was in a 2-for-25 slump two weeks ago. But the talented shortstop has gotten back on track, batting .455 over the last eight games prior to Thursday.

"It was a bad stretch, but I have moved past that," Castro said. "I continued to work hard with [hitting coach] Rudy [Jaramillo] on my mental and physical approach at the plate, and it's been working so far."

The Dominican star has also worked hard to improve defensively. After committing three errors in a game on April 25, Castro has gone 18 straight games without a fielding mishap.

"It's nothing mental or anything that I wasn't doing before," Castro said. "Sometimes things happen in this game that cause you to make mistakes. I'm not trying to blame anything for those errors, but it was raining and the field was wet -- but that's a part of the game. I've been working hard with [third-base coach] Ivan De Jesus to improve defensively."

Marmol shining on the road for Cubs

MIAMI -- Carlos Marmol has been nearly unhittable this season.

The Cubs closer was 1-1 with a 1.42 ERA and had nine saves entering Thursday. But what is most impressive is Marmol's success on the road. The 28-year-old has not allowed a run in his last 21 2/3 innings away from Wrigley Field dating back to last season, but he feels good anywhere he pitches.

"I think I've done well at home and I feel comfortable there," Marmol said. "I feel good on the road as well. I'm doing everything I can to keep putting up zeros, regardless of where we are playing."

Marmol last allowed a run on the road on Aug. 25, 2010, converting all 16 of his save chances since then. His streak is the third best is franchise history. Only Warren Brusstar and Lee Smith have done it for longer, as each posted 24 consecutive scoreless innings in 1983.

Some pitchers have trouble on the road because of unfamiliar conditions, but Marmol credits some of his success away from his home park to his ability to adjust quickly.

"Obviously, when you pitch at home, you know the fans are behind you and you feel more comfortable because you know the field and the mound," Marmol said. "Every player has to play a few days here and a few days there. It's not easy to get used to a different mound every few days, but we all go through it. You just put in your work and make adjustments out there. Things have gone well for me so far on the road."

The hard-throwing right-hander is not the only Cubs reliever having success away from Wrigley. Chicago's bullpen boasted a 2-1 mark with four saves and a 0.41 ERA in its last nine road games entering Thursday.

"We're a confident and talented group," Marmol said. "We're all there for each other and we pick each other up all the time. We know any one of us can go in there in any situation and get the job done. Hopefully, we can stay that way, because it's been working for us so far."

Pena wielding a hot bat for Cubs in May

MIAMI -- Carlos Pena's career as a member of the Cubs did not get off to a strong start. The slugging first baseman hit just .159 with no home runs over the first month of the season, but things have turned around for him since. Pena was batting .327 with five homers in May entering Thursday, but he is not about to get complacent just because he started hitting.

"I'm one of those guys that keeps on coming and working hard," Pena said. "I don't ever think I have it figured out. I just know that the only answer is to keep on working and trying to improve on my weaknesses. I don't sit there and over-analyze anything. I just try to stay consistent with my work and everything will be OK."

Pena hopes to carry his hot hitting into this weekend's series against the Red Sox. The 33-year-old was born in the Dominican Republic but grew up in Massachusetts, so he is well aware of the history between the Cubs and Red Sox.

"I know enough to understand the magnitude of it," Pena said. "I'm really looking forward to it, and I think all the guys are. It's going to be quite an event, and we're not going to take it for granted. Hopefully, we can come out on the winning end."

Even if the Cubs come up short in Boston, Pena is confident that the team will get on track soon, and he can't wait to be a part of what he feels is a special team.

"I think we have a very good group and a very intense fan base," Pena said. "I am still optimistic about this year as far as us as a team. I really want to give the city of Chicago what they've always wanted. To be part of a team with the opportunity to do so, I treat that with a lot of respect and I'm honored to give it a try."

Worth noting

• Cubs assistant general manager Randy Bush refuted a report that the Cubs were interested in Kevin Millwood. "We kicked the tires a while back and there's nothing new to report," Bush said.

• After tossing two-thirds of an inning Wednesday, Sean Marshall has now thrown 18 consecutive scoreless innings. The lefty last allowed a run on September 11, 2010.

• Entering Thursday, Starlin Castro and Marlon Byrd had combined for 108 hits this season, tops by any pair of teammates in baseball. The Dodgers' Andre Ethier and Matt Kemp were second with 107 combined hits.