Keller is listed as the Pirates' probable starter for Saturday's game in Cincinnati, Kevin Gorman of TribLive.com reports.
At least for this week, the Pirates will be sticking with a six-man rotation, allowing Keller and Bryse Wilson to make their second starts with the club after both were recently activated. After a nearly two-month stint at Triple-A Indianapolis, Keller faltered in his return to the Pittsburgh rotation last weekend versus the Phillies. He gave the Pirates five innings but was touched up for four runs on eight hits and no walks while striking out two.