Last season, De La Rosa missed most of the first half because of a finger injury, but he still went 8-7 with a 4.22 ERA in 20 starts for the Rockies. He also recorded 113 strikeouts in 121 2/3 innings. Even more impressive was that he allowed just three runs or fewer in 13 of his last 14 starts.
De La Rosa's best season was in 2009, when he went 16-9 with a 4.38 ERA for Colorado, and that was after he started the season 0-6. He also struck out 193 batters in 185 innings.
De La Rosa is a pitcher whom Nationals general manager Mike Rizzo is familiar with. It was Rizzo, then the scouting director for the D-backs, who signed De La Rosa to his first professional contract in 1998.
Rizzo was unavailable for comment.
Besides his three stints in the D-backs' organization, De La Rosa also spent time with the Red Sox, Brewers, Royals and Monterrey of the Mexican League before finding a home with the Rockies.
If he signs with the Nationals, De La Rosa would likely slot near the top of the rotation.
Washington is also in the Cliff Lee sweepstakes, but a baseball source said the club would not get into a bidding war like it did with first baseman Mark Teixeira after the 2008 season. Washington offered Teixeira the most money, but he elected to sign with the Yankees.
During the uniform unveiling on Wednesday, Rizzo told the local media that he was not going to put "all of my eggs" on Lee. He indicated there were other pitchers he is looking to acquire this offseason.
"We have to take each case individually. We are going to be very realistic on our chances to sign Cliff Lee," Rizzo said Wednesday. "We are going to speak to him and his representative and see where it takes us. We are certainly not going to put our eggs with the Lee basket because we are going to be one of many people trying to acquire his services.
"But we have other irons in the fire. We have a lot of other decisions to make and a lot of other people to talk to. We are going to make a prudent baseball move via free agency or trade. But we are certainly not going to make a move [just to make a move]."
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the time. He also could be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.