"We think for a temporary period of time, this is the right thing to do," general manager Jack Zduriencik said. "It keeps our position players intact, and we feel pretty good about what we're sending to the mound for the next couple of days. You never know, but if we have to make a move shortly after that, we're prepared to do that."
Jackson, 28, went 0-for-5 with a pair of strikeouts in Triple-A Tacoma's 8-5 loss at Omaha on Monday afternoon and was en route from Omaha to Florida on Monday night. He hit .263 in nine rehab games.
Although the Mariners were reluctant to bring Jackson back last weekend and test the ankle on Toronto's soft artificial turf, manager Lloyd McClendon said he'll be used against the Rays, even with Tropicana Field's own artificial surface.
"That's why we called him, to play," McClendon said. "He's our center fielder. From a physical standpoint, he's ready. He's had some at-bats down there. We need him back in the lineup."
Jackson was hitting .242 with 11 runs and a team-leading five stolen bases when he twisted his ankle while stepping on the corner of the first-base bag trying to beat out an infield hit on May 3 in Houston. Dustin Ackley, Justin Ruggiano and Brad Miller have all split time in center field during his absence.
Miller lost his shortstop job to Chris Taylor when Taylor was called up to take Jackson's roster spot earlier this month, but Miller has filled a valuable utility role since then, which is where the situation gets interesting.
The Mariners also have veterans Rickie Weeks and Willie Bloomquist as utility players, and their outfield becomes crowded with Jackson's return. Monday's decision could buy time to continue working trade possibilities, or just to see how things play out with Jackson back with the team.
Farquhar has struggled, with a 6.46 ERA in 20 appearances, a far cry from the 2.66 ERA he put up last season in 66 outings.
"There were a couple outings earlier when I was lost, but I feel like I battled back from that and I'm not too far off," Farquhar said. "It's little things. More cutter command than anything. I'll use this time to get away from the spotlight and go down there and get back to my old self.
"It's not my first time [struggling]. I've been humbled plenty of times in baseball. You just have to forget about it and battle your way through it. Nothing was as hard as when I went to five teams in six weeks in 2012. So I just need to get back into the rhythm, and hopefully I'll be back up here."