The Rays opened a spot in their bullpen for Josh Lueke on Friday by designating veteran reliever Kyle Farnsworth for assignment.

Farnsworth saved 25 saves with a 2.18 ERA for the Rays in 2011, both career bests, but has mostly struggled since. He began last year on the disabled list with a right elbow strain and was relegated to middle relief when he returned, going 1-6 with a 4.00 ERA in 27 innings.

Tampa Bay manager Joe Maddon had even more trouble finding work for Farnsworth this season, and the 37-year-old right-hander hasn't been effective when called upon. In 29 2/3 innings over 39 appearances, Farnsworth put together a 5.76 ERA and 1.48 WHIP with only 19 strikeouts.

The Rays have 10 days to trade or release Farnsworth.

Lueke, meanwhile, will join Tampa Bay for the third time this season. The 28-year-old right-hander has made 11 appearances in the Majors this season, compiling a 3.75 ERA with 15 strikeouts and nine walks in 12 innings.

But Lueke has thrived with Triple-A Durham this year, racking up 70 strikeouts compared to 14 walks over 50 innings of work. In 34 appearances for the Bulls, Lueke owns a 0.72 ERA, 0.96 WHIP and 14 saves.