The Cedar Rapids Kernels and Minnesota Twins announced Thursday that pitcher John Curtiss and infielder/outfielder Trey Vavra have been place on the 7-Day Disabled List.

Curtiss has a right forearm strain. Vavra has a sprained left ankle.

Pitcher Sam Gibbons has joined the Kernels from Extended Spring Training to replace Curtiss.

The Twins signed Gibbons as a non-drafted free agent on July 2, 2011. He spent last season with Elizabethton, posting a 4-5 record and 3.88 ERA in 12 starts.

Curtiss has made seven starts for the Kernels, posting a 2-3 record and 5.87 ERA. He left Monday's game at Beloit in the fifth inning.

Vavra has played in 42 games, batting .342 with six homers and 28 RBIs. He's among the MWL leaders in average, hits and slugging percentage. He sprained his ankle chasing a foul ball during Tuesday's 4-1 win over Wisconsin.