A Denver Post report on its Web site cited a major league source confirming the Rockies put in a claim for the Hernandez.
After the team's 8-2 win over Washington on Tuesday night, Colorado's vice president of communications Jay Alves said the Rockies are looking at Hernandez, but stopped short of confirming the waiver claim.
"There is interest in Hernandez but there's nothing to confirm," Alves said.
The 33-year-old Hernandez was 10-8 with a 5.48 ERA in 139 2/3 innings for the Twins before getting designated for assignment Friday to make room for Francisco Liriano.
Hernandez has allowed 199 hits, by far most in the majors this season. Opponents are hitting .341 against him, highest in baseball against a qualifying pitcher. He has a 6.50 career ERA in 13 starts at Coors Field.
The Rockies have had trouble filling the last two spots of their rotation all season. Valerio de los Santos was optioned to Triple-A on Monday after two unimpressive starts, and Tuesday's starter Jorge De La Rosa has been inconsistent in 15 starts this season.
Before the game, Colorado Rockies general manager Dan O'Dowd would not confirm a report that the team had claimed starter Livan Hernandez on trade waivers Tuesday.
"I can't comment on that," O'Dowd said. "I will say we are looking for another starting pitcher."