Lind was optioned to triple-A Las Vegas on May 17 after batting .186 with three home runs and 11 RBI in 34 games for the Jays.
The move takes Lind off the 40-man roster to make room for Coello.
"We needed a spot on the (rotation), so we put (Lind) on waivers a few days ago and he cleared," Blue Jays GM Alex Anthopoulos said on a conference call Thursday. "Whenever he finds his way back here we'll just clear a spot again."
Coello, a 27-year-old righty, is 3-1 with a 3.22 earned-run average in 17 games with Las Vegas.
Toronto had a spot to fill after left-hander Aaron Laffey was optioned to Las Vegas following Wednesday's 4-1 win over Baltimore.
Laffey, 27, has yet to make an appearance with the Jays this season despite callups in April and May. He is 2-5 with a 4.88 ERA in nine starts for Las Vegas.
"Aaron and Robert, either one could have been up here," Anthopoulos said. "It just got to the point where we needed to get Aaron back into the rotation otherwise it didn't make any sense. The longer he sat here, the further behind he would have been to continue to be a starter option for us down the road."
Anthopoulos said Lind was responding well to being sent Las Vegas.
"He thinks his timing is a lot better and he thinks so far it's going very, very well for him," Anthopoulos said. "His confidence is definitely in the right place, and he feels he's made a lot of changes and adjustments and he's on the right path."
Anthopoulos also said he didn't put much stock into Baltimore pitcher Jason Hammel's assertion that the Blue Jays were stealing signs. Hammel gave up four solo homers in the Orioles' 4-1 loss to the Jays on Wednesday.
"Our players, when they have a bad game, they choose to answer the questions and they blame themselves," he said. "They take accountability and that ends up being the end of it.
"How other players want to handle things is their choice."