There is still no defined timetable for Morrow's return, but the Blue Jays should have a better idea of his progress before the end of August.
"He has been throwing some sides without his finger guard and he's feeling better," Blue Jays manager John Gibbons said. "He's cutting it loose better. It's not full-go, but it's progress."
Morrow could be entering the final month of his career in a Blue Jays uniform. Toronto has a $10 million option on Morrow's contract for next season, but it's becoming increasingly likely the club would instead choose to buy him out for $1 million.
The 30-year-old has yet to make it through a full season as a starter. Last year, he was limited to 10 starts, and this year he made six before going on the disabled list.
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. This story was not subject to the approval of Major League Baseball or its clubs.