Silva was scheduled to take the mound against the Blue Jays on Saturday afternoon, but instead will have his spot filled by knuckleballer R.A. Dickey.
The news isn't all bad for Seattle, though, as Silva's injury isn't considered serious and he's expected to be able to start on Tuesday against the Rangers.
The 29-year-old will throw a side session on Saturday before departing for Texas on Sunday night. Mariners manager Jim Riggleman is hopeful that having a full 24 hours of rest before sitting through a long plane ride will help his starter get back to full strength.
"Before he flew here, he threw his side and then got on the plane," Riggleman said prior to the opener of a three-game series in Toronto. "So we're just trying to put a day in between when he throws and when he travels."
Silva began feeling the effects of the injury during his last outing against the Indians on July 20. In that start, Silva exited after three innings having surrendered four runs on four hits.
Riggleman says Silva lobbied to remain the starter for Saturday's game, but the team opted to err on the side of caution just to make sure the soreness in Silva's lower back doesn't linger for an extended period of time.
"He was saying: 'Okay, if not tomorrow, then don't wait until Tuesday, I'll pitch Monday,'" Riggleman said. "We're just going to force him into an extra day."
The Mariners can ill afford to lose another member of their starting rotation for much longer than that. Left-hander Erik Bedard currently is on the 15-day disabled list with a stiff left shoulder and the team already spent time without No. 1 starter Felix Hernandez earlier this season because of a sprained ankle.
Seattle does have the luxury of turning to Dickey to make Saturday's start. The 33-year-old will be pitching on just three days' rest, but because he primarily throws knuckleballs the task should be much easier to accomplish.
His last outing came against the Red Sox on July 22, when he surrendered four runs over six innings. It was the first time in six outings Dickey surrendered more than two runs during a start.
That outing came on just two days' rest and on Friday afternoon, the native of Tennessee said he usually requires just one full day of rest before he feels like he is back to 100 percent.
"My style helps to make pitching on short rest a lot easier," Dickey explained. "Throwing knuckleballs at around 75 percent intensity for 80 percent of the game helps in recovery. I don't expect to go out and be less than 100 percent."
Gregor Chisholm is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.