Leeds United's Luke Ayling impressed on Saturday.
Ayling impressed on Saturday as Leeds bounced back from a disappointing 4-1 defeat at Wolves by beating Barnsley 2-0 at Oakwell in a Yorkshire derby, setting up Egzjan Alioski's goal.
Things haven't been great for the former Bristol City man - who joined for £750,000 under Garry Monk - and he has struggled for consistency this season after a superb first year at Elland Road.
At Wolves, Ayling was partially responsible for at least one of the four goals that the Whites conceded, but Whelan believes that his performance at Oakwell is evidence that he's getting back to his best.
He told BBC Radio Leeds: "He looked back to his best. He stepped back up again, driving forward, defending back to what we expect from an Ayling performance.
"He's just got so much energy.
"That's the thing I like about him. He wants to get forward, join in the play, link up and he causes problems down that right hand side – but he does his defensive duties as well."
Ayling and Leeds will certainly need to improve on their consistency over the next month or so as Thomas Christiansen's side face seven games in 31 days.