Motter was optioned to Triple-A Tacoma on Tuesday.
Motter was sent down in order to clear room for spot starter Ariel Miranda. The utility man's performances haven't merited a demotion, as he hit .267/.353/.467 over 17 plate appearances, but he's a fringe player with options remaining, so he ended up being the odd man out. He could be shuttling back and forth along Interstate 5 a lot this season. His 10 homers and 12 steals in 390 career plate appearances make him an intriguing budget power-speed option during his stays with the Mariners, though his .198 career batting average gives him a pretty low floor.