CHICAGO -- Matt Garza was with the Cubs on Thursday at Wrigley Field, three days after the right-hander was shut down indefinitely with a stress reaction in the back of his right elbow.

Garza said his goal is to get back on the mound this season, despite there being no official timetable on his return.

"I'm hoping," Garza said. "That's why I'm working my tail off. Doing everything I can."

Garza hasn't pitched since he left his July 21 outing after three innings because of cramping in his right triceps. He threw a bullpen session Saturday in Los Angeles, but his arm was stiff Sunday and he returned to Chicago to be examined. The results were discovered Monday.

The 28-year-old right-hander said he was surprised at the diagnosis of the injury, which he originally thought was just a sore muscle.

"I was throwing through this thing. I thought it was just another slow bump, I'd be fine and keep going," Garza said. "But the doctor said that we've got to shut it down, and you've got to listen to the doc."

Garza won't be allowed to pick up a baseball for the next two weeks. He admitted he hasn't been in the best of moods because of that, which was evident to Cubs manager Dale Sveum when he saw him Thursday afternoon.

"He wasn't in the typical Matt Garza spirits, that's for sure," Sveum said.

Garza didn't try to hide his disappointment.

"It [stinks]," Garza said. "They're not letting me throw a ball. That's what I get paid to do, so it's not fun to come here and sit down.

"Yeah, I get to work out and ride a bike and watch a ballgame, but it's still not what I like doing. I like being out there taking control of the game and being able to do what I get paid to do."

Vitters, Jackson embrace first Wrigley experience

CHICAGO -- Josh Vitters took batting practice at Wrigley Field shortly after the Cubs selected him No. 3 overall in the 2007 First-Year Player Draft.

Because of rain, the young third baseman didn't get to take it again Thursday -- his first game in Chicago as a member of the Cubs -- but he's looking forward to it.

"Just to be out here and be part of the team this time and not just taking BP for getting drafted in the first round, it's really great to have earned my way here," said Vitters, ranked by MLB.com as the Cubs' No. 11 prospect. "Hopefully I'll be here for a long time to come."

Vitters and center fielder Brett Jackson -- the club's 2009 first-round pick and top-ranked prospect -- joined the Cubs on the team's West Coast trip. With a few games under their belts as Major Leaguers -- four for Vitters and three for Jackson -- they came to Wrigley Field on Thursday for the first time as Cubs.

Jackson was in Thursday's starting lineup, playing center field and batting seventh, while Vitters sat against Reds right-hander Mike Leake.

Jackson admitted his first few days in the Majors -- which included traveling to Los Angeles, San Diego and Chicago -- were a whirlwind.

"I finally got a little sleep the last couple nights, which is nice," Jackson said. "I'm starting to settle in a little bit. This is a whole new experience, though, playing in Chicago tonight. I kind of got settled in in San Diego and then kind of getting that adrenaline, that excitement again tonight. But it's been a fun few days."

Both players figure to see plenty of playing time during the remainder of the season as the Cubs continue to look toward the future. Vitters said he was told he'd play mostly against left-handed pitchers and sparingly against righties, while Jackson should get plenty of big league experience while honing his swing (eight strikeouts in 11 at-bats entering Thursday).

The fact that the two of them get to experience the excitement -- and struggles -- of their callup together is a bonus.

"We always talked about it, the last few years, we were talking about how awesome it would be to be called up together," Vitters said. "I think that's just the perfect way to come in."

Clevenger ejected for arguing balls and strikes

CHICAGO -- Cubs catcher Steve Clevenger was ejected by home-plate umpire Jeff Nelson in the fifth inning of Thursday night's 5-3 win over the Reds for arguing balls and strikes.

With a runner on first and one out and the Cubs trailing, 3-1, Reds right-hander Mike Leake threw a 1-1 fastball to Clevenger, who took the outside pitch, which was ruled a strike by Nelson.

Clevenger -- who also appeared to be upset when he was called out looking in the second inning -- argued with Nelson before being ejected.

"I think the first pitch, obviously, he wasn't happy with," Cubs manager Dale Sveum said. "He's got to have a little more composure than that when he's a catcher. You can't be getting thrown out of games like that for situations like that."

Welington Castillo replaced Clevenger and proceeded to strike out swinging. The strikeout was charged to Clevenger.

Worth noting

• The Cubs promoted Cuban outfielder Jorge Soler to Class A Peoria on Thursday. Soler, whom the Cubs signed to a nine-year, $30 million deal in July, was hitting .241 (13-for-54) with two home runs, two doubles and eight stolen bases in 14 games for Rookie-level Arizona. He also posted a .328 on-base percentage and slugged .389.

"It's interesting to see [young players] in a different atmosphere," Cubs manager Dale Sveum said. "There's fans in the stands, and it's just a little more baseball-oriented instead of kind of an instructional league atmosphere."

• Thursday was the 24th anniversary of the first "official" night game at Wrigley Field, a 6-4 Cubs victory over the Mets on Aug. 9, 1988. The originally scheduled first night game was set for the previous evening, but was postponed because of rain.