The Cubs signed Boyd to a two-year, $29 million contract Monday, Jon Heyman of the New York Post reports.
Boyd will start Thursday in Game 3 of the ALCS against the Yankees, Mandy Bell of MLB.com reports.
Guardians manager Stephen Vogt said Friday that Boyd will start Saturday in Game 5 of the ALDS against the Tigers, Mandy Bell of MLB.com reports.
Boyd is expected to start for Cleveland in Game 2 of the ALDS versus Detroit, Chris McCosky of The Detroit News reports.
Boyd escaped with a no-decision in Monday's 4-3 win over the Twins, giving up three runs (two earned) on five hits and three walks over 2.2 innings. He struck out five.
Boyd (1-1) took the loss Saturday as the Guardians fell 3-0 to the Pirates, allowing one run on four hits over six innings. He struck out eight without walking a batter.
The Guardians activated Boyd (elbow) from the 15-day injured list Tuesday.
Boyd (elbow) struck out seven and while giving up one hit and no walks over six scoreless innings in his rehab start Wednesday with Triple-A Columbus.
Boyd (elbow) is scheduled to make another rehab start for Triple-A Columbus on Wednesday, Chris Assenheimer of the Elyria Chronicle-Telegram reports.
Boyd (elbow) struck out five over 3.2 innings and gave up two runs (one earned) on two hits and no walks in his rehab start Thursday with Triple-A Columbus.