Gallen (elbow) is scheduled to throw a bullpen session Tuesday, Zach Buchanan of The Athletic reports.
The Diamondbacks cleared Gallen to take the next step forward in his rehab program for a UCL sprain after he played long toss from 90 feet Monday with no renewed discomfort. Gallen will need several weeks to build up to a starter's workload before being ready to rejoin the Arizona rotation, assuming he can steer clear of any setbacks along the way. Fantasy managers shouldn't expect him to be reinstated from the 10-day injured list until late June at the soonest.