The Potters star was on the receiving end of the Croatia international's late challenge at The Reebok, which earned him a second yellow card from referee Peter Walton.
It came just three minutes after Klasnic had volleyed a late winner - his first Premier League goal of the season - to send Wanderers seventh in the table.
While Delap confirmed contact with the elbow had been made, he conceded the Whites frontman was unlucky to have been booked.
He told the Bolton News: "We were both looking at the ball, but he caught me. Maybe it was harsh on him and should have been a free-kick, but not a booking, but that's what you get these days."
Long-throw specialist Delap also inadvertently had a hand in Klasnic's goal, after failing to clear Gretar Steinsson's throw.
"I headed it and it hit Abdoulaye Faye and dropped straight to Klasnic," he said. "The throws are hard to deal with, but if you get the first header, then most of the time the other team won't score."