DENVER -- Jason Giambi insists he won't mind being a backup in a new league.
"There is no small role when you're in a pennant race," the former AL MVP said Tuesday after the Colorado Rockies added him to their roster.
Giambi, who has never played in the National League, gives the Rockies another veteran leader in the clubhouse, a powerful pinch-hitter and an accomplished first baseman who can spell Todd Helton at times.
Manager Jim Tracy has tried to give Helton regular rests this season so he doesn't have a recurrence of the back problems that plagued him last season. Before Giambi's arrival, that always meant juggling his lineup and the defense.
"I'm excited to be here, come and just fit in, be part of a team, especially a team in the pennant race and as great a team as they have clubhouse-wise," Giambi said. "Talking to Todd, I remember talking to him playing against them this year, and he just said the group of guys is incredible here. That's one of the things that steered me toward here, getting a chance to play with these guys."
Giambi made his Rockies debut in the seventh when he batted for the pitcher with the bases loaded and drew a four-pitch walk from Sean Green as the Rockies beat the New York Mets 8-3. Colorado took a one-game lead over the San Francisco Giants for the NL wild-card lead.
The 38-year-old Giambi signed with the Rockies on Aug. 24 and reported to Triple-A Colorado Springs, where he hit .444 (8-for-18) with four RBIs and six walks in six games. He hit homers in back-to-back games Aug. 29-30.
"I wanted to get back in the swing of things. I had been out for almost a month. It was nice to get down there, get playing baseball again," Giambi said.
Giambi was cut by Oakland last month after hitting .193 with 11 home runs and 40 RBIs. He had been on the disabled list because of a strained right quadriceps before the Athletics released him, cutting short the struggling slugger's return to his first major league club.
A five-time All-Star, Giambi had returned to Oakland this season after seven seasons with the New York Yankees and spent plenty of time at DH, something the NL doesn't have.
"That's one of the things I focused on when I was down in Colorado Springs. I got a chance to DH a few roles down there, so I kind of took every at-bat like it would be a pinch-hit at-bat," Giambi said. "It definitely helped out."
Although he has played all 1,933 games of his career for American League teams, Giambi has a .274 batting average with 44 home runs and 137 RBIs in 193 games against NL clubs in his 15-year career.
Tracy said if the Rockies did reach the playoffs, Giambi, who has a .289 average in 42 postseason games, could be on the 25-man roster for the postseason even if he doesn't get much playing time in September.
"I'm excited," Giambi said. "Hopefully, I can bring that lightning in the bottle in National League parks, if we get guys on, hit a big three-run homer, or even give a good at-bat and get on base. With the speed that a lot of National League teams have, it makes a huge difference sometimes."
At least once face was familiar when Giambi walked into the clubhouse Tuesday. With uncertainty surrounding injured right-hander Aaron Cook, the Rockies acquired right-handed starter Jose Contreras from the Chicago White Sox for minor league pitcher Brandon Hynick and cash on Monday.
Contreras and Giambi played together with the New York Yankees.
"He had a great year for us in New York, he had some great years in Chicago. He can come in here and he might get a breath of fresh air," Giambi said. "He can be unbelievable. He's got phenomenal stuff."
Tracy said he'll start Contreras on Saturday night against Arizona.
"He completely understands this time of the season," Tracy said. "You're talking about a guy who's pitched in the World Series, he's pitched in playoff games, he's pitched obviously in important September baseball games. He hasn't completely been himself this year but I've seen this scenario play itself out to a positive more than once where a guy gets a little bit of a change of scenery."
The Rockies also added right-hander Joel Peralta, left-hander Randy Flores and catcher Paul Phillips to their roster on Tuesday. To make room, they recalled pitchers Greg Reynolds and Greg Smith and placed them on the 60-day disabled list.
Information from The Associated Press was used in this report.