Sources: Penny intrigues 2 NL teams

As Brad Penny, who was officially released by the Boston Red Sox on Thursday, is being moved through waivers, National League playoff contenders San Francisco and Florida have expressed interest in the veteran right-hander, sources said.

Those teams and any interested AL teams probably won't want to claim Penny off waivers, because the cost of Penny as a short-term hire would be enormous. Penny is still owed about $1 million in salary for the rest of this season, and he has $500,000 in bonuses as he reaches 160 innings, 170, 180 and then 190. Penny has thrown 131 2/3 innings this season, which means that if he were to accumulate 50 innings over eight starts, he would cost an additional $1.5 million.

But the interested teams probably would like to have him after he clears waivers, which could be on Monday. If Penny clears waivers, he would cost any team that acquired him only about $100,000 for the rest of the season.

The Colorado Rockies expressed interest in Penny initially but will not pursue him either through waivers or if he becomes a free agent at the end of the waiver process, sources said later Thursday.

Because Penny is being passed through release waivers, he has the right to decline any waiver claim, and essentially force his way into free agency. But in order to do that, he would have to walk away from the incentives in his contract that could be worth as much as $1.5 million.

Reportedly, the Minnesota Twins are considering claiming Penny on release waivers. When the pitcher passed through waivers earlier this month and was claimed, the team that claimed him was the Yankees.

Penny is healthy and could join a rotation immediately, after going 7-8 with a 5.61 ERA. He played five seasons for the Marlins earlier this decade, and he could benefit from the Giants' big ballpark.

With the release of Penny on Thursday, the Red Sox activated reliever Billy Wagner, moves that come two days after Boston obtained Wagner in a trade with the New York Mets.

The best possible situation for Penny to showcase himself for another round of free agency this fall might be with the Rockies, who are currently leading the NL wild-card race. Penny has fared well in Coors Field, posting a record of 6-1 with a 3.92 ERA in 11 career starts. The Rockies have been looking for an alternative to Josh Fogg for their rotation, as they await the return of injured starter Aaron Cook, who may not return until mid-September at the earliest.

The Rockies and the Giants might find this fact about Penny intriguing, as well: He left the Los Angeles Dodgers on very bad terms after last season and would undoubtedly compete against them with a significant competitive chip on his shoulder.

The Tampa Bay Rays and Texas Rangers are among the AL teams that might have interest in the right-hander, but it might make more sense for him at this point to go to the National League -- as it has seemingly helped Cliff Lee and John Smoltz, who both moved from the AL to the NL in the past month.

Buster Olney is a senior writer for ESPN The Magazine.