Lopez (4-2) earned the win Thursday over the Mariners, allowing one run on four hits over 6.1 innings. He struck out 10.
Lopez didn't factor in the decision Wednesday against the Orioles after he gave up one run on two hits and no walks over six innings. He struck out seven.
Lopez and the Twins will not play Thursday after their game against the Tigers was postponed because of inclement weather.
Lopez (1-1) took the loss Thursday versus the Guardians, allowing four runs (three earned) on six hits and a walk over 5.2 innings. He struck out two.
Twins manager Rocco Baldelli named Lopez the team's Opening Day starter Wednesday, Lexi Schweinert of Twins Radio reports.
Lopez will start Game 2 of the Twins' ALDS matchup against Houston on Sunday, Betsy Helfand of the St. Paul Pioneer Press reports.
Lopez will start Game 1 of the Wild Card Series for the Twins, Do-Hyoung Park of MLB.com reports.
Lopez (10-8) took the loss Saturday, giving up five runs on eight hits over five innings as the Twins fell 7-6 to the White Sox. He struck out eight without walking a batter.
Lopez allowed two hits over eight shutout frames in Sunday's loss to the Mets. He struck out 14 and did not factor in the decision.
Lopez (8-6) picked up the win in Saturday's 8-1 victory over the Phillies, allowing four hits and a walk over six scoreless innings. He struck out seven.