The Pirates transferred Velasquez (elbow) to the 60-day injured list Friday, Alex Stumpf of DKPittsburghSports.com reports.

Velasquez underwent season-ending surgery Friday on his right elbow, Jason Mackey of the Pittsburgh Post-Gazette reports.

The Pirates placed Velasquez on the 15-day injured list Sunday with right elbow discomfort, Justice delos Santos of MLB.com reports.

Velasquez was removed from Saturday's start against Seattle with right elbow discomfort. He allowed four runs on seven hits over two innings with three strikeouts and one walk before exiting, Justice delos Santos of MLB.com reports.

Velasquez (elbow) will return from the 15-day injured list to start Saturday's game in Seattle.

Pirates manager Derek Shelton confirmed Wednesday that Velasquez (elbow) will return to the rotation this weekend in Seattle, Justice delos Santos of MLB.com reports.

Velasquez (elbow) returned to Pittsburgh on Wednesday and expects to be activated from the 15-day injured list to make a start at some point during the Pirates' upcoming series in Seattle this weekend, Jason Mackey of the Pittsburgh Post-Gazette reports.

General manager Ben Cherington said Sunday the Pirates have yet to decide if Velasquez (elbow) will require a second minor-league rehab start, Justice delos Santos of MLB.com reports.

Director of sports medicine Todd Tomczyk said that Velasquez (elbow) will throw a side session Wednesday and make a rehab start later this week, Jason Mackey of the Pittsburgh Post-Gazette reports.

Velasquez (elbow) is expected to begin a rehab assignment with Triple-A Indianapolis later this week, Jason Mackey of the Pittsburgh Post-Gazette reports.