The 25-year-old Canadian said all went well with his initial throwing session and he'll be re-evaluated Saturday.
"It actually felt fine," Paxton said. "I was letting it go pretty good from a 45-foot distance. I didn't want to light up Waits, so I just kept it nice and easy, just making sure I could stay fluid. It felt good, so it was positive."
Paxton said he'll throw again from 45 or 60 feet if he feels fine on Saturday, then will sit down with the training staff and put together a throwing program to rebuild his arm strength before eventually going out on a Minor League rehab stint.
"It's tough not to get too excited, but you just have to take it easy and trust the process and just take it one day at a time," he said.
Teammate Taijuan Walker is scheduled to begin throwing Monday as he's on a similar return after being shut down with an impingement in his right shoulder that put a halt to his Minor League rehab stint.
Blake Beavan is also awaiting word on when he can start throwing again after going on the 15-day DL with right-shoulder tendinitis after he lasted just four innings when he was called up to replace Paxton on April 15.
"The plan so far is to start throwing next week and then when the team gets back from the road, start throwing bullpens and see how I react to that," said Beavan, who hopes to be ready for a Minor League rehab assignment sometime in mid-to-late May if all goes well.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.