Jackson agreed to a one-year, $7.7 million contract with the Mariners on Monday, Jon Heyman of CBS Sports reports. Jackson posted another solid season split between the Tigers and Mariners, but saw his numbers drop off with after being traded to Seattle. In 54 games with his new club, he finished with a .229/.267/.260 batting line without a home run and just 14 RBI over 223 at-bats. He will enter 2015 as the everyday center fielder for the Mariners.