''Sub-standard display' ... Paul Warne's honest reaction to Rotherham United's win over Scunthorpe United

The League One Millers saw off League Two's basement club, Scunthorpe United, 4-1 at AESSEAL New York Stadium to progress from the group stages of the tournament with a game to spare.

But Warne was unhappy with his team's performance on a rain-sodden evening, accusing them of "taking their foot of the gas" after sweeping into an early two-goal lead.

"Josh Vickers was probably out best player tonight," the manager said. "That's an indictment of how we played, I suppose.

"Scunthorpe were excellent. They kept the ball well and caused us no end of problems. We made loads of little sloppy mistakes - not picking up people at throw-ins, not winning tackles.

"I thought we were good for the first 20 minutes and looked like we were going to be on top but then maybe the lads sub-consciously took their foot of the gas a little bit."

Goals from Will Grigg and Freddie Ladapo put the home side 2-0 in front by the 20th minute and late strikes from Hakeem Odoffin and Michael Smith rounded things off after Ryan Loft had given Scunthorpe hope on the hour mark.

The Millers are flying in League One but didn't produce the form they have shown in their last few matches when it came to Papa John's competition.

"It's a difficult one," Warne said. "In the famous words of John Breckin, you can't turn it on and off. You have to have it all on or you're in trouble. We performed a bit below the standards we've set ourselves in the second half.

"We got two late goals and that probably flattered us. We created the best chances of the game but I always want more. We did enough to win.

"Football is about winning. The strikers all scored and Haks got a goal. They were the positive things."