Cooper started the Championship game against Bolton at Elland Road, but he was forced off at half time due to a hamstring injury.
Former Leeds striker Whelan seems to have been impressed with the first-half performance of the 24-year-old defender.
“Liam Cooper has been the main one who is getting across the men and he set up the goal, because he wanted it,” Whelan told BBC Sport (15:52).
During his time on the pitch, Cooper took two shots, had a pass accuracy of 87%, created one chance, attempted one dribble, won 100% of his headers, and made three interceptions, three clearances and two blocks.
Leeds are 16th in the Championship table at the moment with 41 points from 34 matches, nine points above the relegation zone.
Steve Evans’s side will return to action on Tuesday evening when they take on Cardiff City away from home at the Cardiff City Stadium in the Championship.
Cardiff are currently seventh in the league table with 55 points from 35 matches, level on points with sixth-placed Sheffield Wednesday.