According to a major league source, Bobby Jenks’ contract — which is guaranteed to pay the reliever $6 million per season for the next two years — also includes some noteworthy bonuses. The 29-year-old can earn up to an additional $1 million by finishing games, specifically: $200,000 each for 30, 40, 50, 55 and 60 games completed.

(The last time the Red Sox issued such bonuses to free-agent relievers other than Papelbon were to Joel Pineiro and J.C. Romero, both of whom were considered candidates for the closing job when it appeared Papelbon might go into the starting rotation.)

Red Sox general manager Theo Epstein said Tuesday that the plan is for Jenks to be setting up closer Jonathan Papelbon for the 2011 season.

“We feel really lucky that Bobby wanted to pitch here and we were able to get someone of his caliber to join our bullpen and help Dan Bard set up for Pap,” Epstein said.

“It’s not everyday you can bring someone of this caliber without a closer opening. We felt lucky that it happened. Bobby is someone that has great stuff, but we see him as more than just a thrower. He really knows how to pitch, as well. He goes right at guys and throws strikes. He brings the kind of fearlessness to the mound we look for in a market like Boston. We think that he’s going to fit in great and hopefully be part of a pen that’s going to be one of the best ones we have around here in a long time.”

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