Boston Red Sox third baseman Brock Holt (not pictured) grounds...

Boston Red Sox third baseman Brock Holt (not pictured) grounds out to first against New York Yankees first baseman Alex Rodriguez in the first inning in a baseball game at Yankee Stadium on Saturday, April 11, 2015. Credit: Kathleen Malone-Van Dyke

Converted centerfielder Mickey Mantle spent the last two years of his Yankees career playing first base -- and made 23 errors in 262 games. Alex Rodriguez became the team's most unlikely player since Mantle to play the position when he started at first against the Red Sox on Saturday.

He wasn't Mantle, but he also wasn't Don Mattingly. Give Rodriguez an A for effort, but also an E for committing one of three errors by the Yankees.

"It was a lot of action over there today,'' Rodriguez said. "Not that I need more evidence to tell you how great Mark Teixeira is and has been for so many years. I had more action. My head is just spinning.''

Rodriguez got the spot start in place of Teixeira, who turned 35 on Saturday and played every inning of the 19-inning loss to the Red Sox Friday night into yesterday morning.

A-Rod was involved in two key plays. In the second inning, Mike Napoli hit a routine grounder to short and Didi Gregorius made a shin-high throw to first that was dropped by Rodriguez. "The ball should be caught,'' Rodriguez said. "I mean 10 out of 10 [times].''

Napoli later scored an unearned run on Daniel Nava's two-out double off Adam Warren. "I cost Adam probably another 15 pitches on that,'' Rodriguez said. "That was costly.''

With two outs in the eighth, Nava's grounder to third was fielded cleanly by Chase Headley, but he made a high throw to first. Nava was called out, but the Red Sox asked for a review and the replay showed that Rodriguez did not keep his foot on the base. Three more unearned runs scored after that.

Headley was charged with a throwing error, but a more experienced first baseman likely would have made the play.

"We all saw it. Obviously, I was off,'' Rodriguez said. "I've never even done that play in my life, so some of the guys were asking me if I kept my foot on it and I told them I thought I did, but I don't have any history so that was the first time . . . ''

Joe Girardi, who had plenty of other fielding lapses to explain, said of Rodriguez, "He dropped the one ball; besides that, he was fine. That turned into a run for them early in the game. That's not what we expected -- to be difficult catching it -- but it happens.''

It is uncertain how many more times Rodriguez will be penciled in at first, but he wants to be prepared. "I do feel comfortable, relatively speaking,'' he said. "I think one of the things that I'm going to have to continue to work on early every day is you have to know your infielders just like a catcher knows his 12 pitchers. Every guy has a different touch, arm strength, the ball moves differently, and that's going to have to be my job early to realize what the pattern is for each guy.''

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