Mengden was officially recalled from Triple-A Nashville ahead of Saturday's start against the Red Sox.
The 23-year-old returns, as expected, to take on Rick Porcello and the Red Sox in his first major league start since July 25. Mengden failed to go more than five innings in any of his final four starts prior to his demotion, allowing a total of 19 earned runs over 17.2 innings during that span. Most in mixed leagues will want to take a wait-and-see approach.