Millen delighted with City win
City went ahead after three minutes when Jon Stead latched onto Albert Adomah's mishit cross-shot for a tap in.
Brett Pitman doubled the advantage 11 minutes later, rounding goalkeeper Matt Duke and then managed to find the net from a very acute angle before Jamal Campbell-Ryce smashed home from 18 yards.
City's performance left Millen pleased with his teams' attitude.
"I thought the attitude of the players was first class," the City boss told reporters. "We all wanted to produce a display worthy of the chairman's last game and that's what happened.
"To have reached 60 points after earning just six from our first 11 games offers great encouragement for next season.
"We scored two early goals and I knew that if we made a good start it could knock the heart out of Hull in a final game where they didn't have much to play for.
"It was nice to do our end-of-season lap of honour with the chairman on the back of such a good win and I believe we can be a promotion force next season with the right additions during the summer."
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