Jordan Zimmermann, who will be a free agent this coming winter, will be on the mound for the Washington Nationals against the Boston Red Sox on Tuesday evening.

Zimmermann is reportedly unwilling to discuss an extension with the Nationals.

Mike Rizzo admitted on Monday that he had many discussions with Ben Cherington this past offseason and while "sometimes it looks like a reasonable matchup on paper, it just doesn't work out."

Washington received good offers for the right-hander, but none good enough for Rizzo to pull the trigger. The Nationals had interest in some of Boston's position players.

"I don't think we laughed away any of them," Rizzo said. "We took them all serious. We were fortunate to be in a position where we didn't have to move the player and if we would've got the right deal we would've. The right deal is in the eye of the beholder and we felt like we needed to get legitimate value for who Zimmermann was, and not the fact that he has one year left of control.

"But there were no foolish trade discussions or anything like that. Our feel was, it had to fit what we were trying to do. Boston’s feel was, it had to fit what they were trying to do, and sometimes they match up and sometimes they don't."