The young defender, still just 20, capped a tough first half in our 2-1 defeat by giving away a penalty and was substituted at half-time with boss George Graham admitting he looked ‘a little nervous’.
It was a change in fortunes for Thelwell whose fine form since being handed his Premiership debut back in November was rewarded by a first England Under-21 cap last week.
Goalkeeper Sullivan insisted: “Alton’s still young, he’s still learning his game and he’s a good player. He’ll bounce back from that.
“He’s a strong character and I’m sure he can’t wait for the next game to come along to get back in the side and show everyone how well he can do.”
Thelwell’s defensive partner Gary Doherty echoed those thoughts: “Alton was playing on the left-hand side (of a central three) and that is hard — obviously I’ve done it myself and it is tough when you are right footed.
“He was a bit unlucky with the goal and he will bounce back. I’m sure he won’t let it get him down.”
For Sullivan, a spectator for most of the second half as we pinned Rams in their half, it was another frustrating afternoon.
“We didn’t start the best,” he said. “The first 45 minutes we let ourselves down a bit and got caught by two set-pieces.
“In the second half we came out, battled away, got the goal back and created a few chances. We just didn’t get the bounce of the ball. Credit to Derby, they defended well when they had to but the damage was done in the first half.
“But we have to look forward. We’ll work hard this week and work towards getting a result at West Ham next weekend.”
Neil Sullivan is backing Alton Thelwell to bounce back from his Derby disappointment.