Garciaparra had worked out at third on Thursday, but dealing with a slug bunt wasn't one of the things the Cubs covered.
"That's a play that you never see -- a slug bunt," Cubs manager Dusty Baker said. "How do you practice for a slug bunt? It was a great defensive play by Nomar to stop the ball and a good play by Juan Pierre."
"It was a strange one," Garciaparra said of the play. "It comes with learning the position. I probably should've just held onto the ball and gone from there. I think it was definitely an experience, a learning experience, and we'll see if they keep me out there."
Garciaparra is expected to get another chance. Ramirez was placed on the disabled list Friday with a strained left quadriceps, and shortstop Ronny Cedeno was called up from Triple-A Iowa to take the roster spot.
The hot corner has been tough spot for the Cubs to fill since Ron Santo last played there in 1973. Santo played in 2,102 games over 14 seasons. Garciaparra is the 103rd player to start at third for the Cubs since Santo left and the fourth this year. So far, Ramirez, Jose Macias and Enrique Wilson have each started at least one game at third. Neifi Perez also played one inning at third.
Macias gave Garciaparra some tips during batting practice on Friday.
"I told him to be ready and that you don't have time to move your feet," Macias said.
And the error? Macias said that was because of inexperience.
"When you're a shortstop, you know when you can hold the ball," Macias said. "It's happened to me. When you play third base, you have to adjust quicker."
Garciaparra did make a good stop on Juan Encarnacion's line drive to open the seventh, and then he was lifted in a double switch.
"It's a tough situation we're in when guys have to jump around like that, especially him never playing there before," Cubs pitcher Glendon Rusch said.
Friday was Garciaparra's first start this week. He has been bothered by back spasms but told Baker on Wednesday he would play third if needed. Shortstop requires more lateral movement, which could aggravate his back.
"I said, 'I'm here to help the team any way I can,'" Garciaparra said Friday. "I said, 'If Rammy's out of it and he's done, do you want me to play third? That way I can help as best I can.'
"[Baker] looked at me and said, 'Are you serious? How many games have you played there?'" Garciaparra said. "I said, 'I hope you're not talking professionally.'"
Garciaparra, 32, hasn't played third base since his freshman or sophomore year in high school. He came out on Thursday's off-day to work with infield coach Chris Speier and Baker, and he arrived Friday to see his name in the lineup against the Florida Marlins.
"It should be less strain on his back than playing short," Baker said. "There's less ground to cover, less work, new position. Most of the time, if a guy can play short, he can play anywhere in the infield."
In Garciaparra's career, which began in 1996 with the Boston Red Sox, he has played 1,024 games at short and one inning at second. He's committed 145 errors for a .968 fielding percentage. What's the biggest challenge of playing a position he hasn't played since high school?
"Remembering how to do it, I guess," he said. "Every position is important; every position is different. I'm going to go out there and do my best and help in any way possible."
He'll have to react quicker, be ready for bunts -- especially by the speedy Marlins, which he found out in the third inning on Friday. And throwing is a little different.
"He has plenty of arm strength," Baker said. "It's just a matter of him getting accustomed to being that close to the batter."
"It's a different angle," Garciaparra said of throwing. "There are a lot of different things to consider, and you have to experiment in the middle of the season. With all the injuries and all the stuff this team has gone through, that's what you do. You have guys like Woody [Kerry Wood] -- he goes to the bullpen. That says a lot about this team. No one's given up.
"I think everyone on this team is doing whatever they can and whatever is asked of them," Garciaparra said. "I'm the same way."