We took the lead at the Lane through Steffen Iversen in the 1-1 draw but Celtic, who hit the bar in the first minute, hit back through Shaun Maloney and created the better chances in the first half.
"The first half was very frustrating for everyone," said Teddy. "It wasn't the best. We came in and the manager had a few harsh words.
"We didn't get going at all, didn't get into a flow and with the pitch so true, there were no excuses. We were lucky to come in a 1-1 at half-time."
It was a different story after the break and despite Celtic's fitness levels, we finished as the side most likely to score - Teddy hit the woodwork and was denied by Marcus Hedman late on.
"The second half was very good," added Ted. "We had a lot of good chances and when we changed the system, it worked even better.
"All in all I thought it was very competitive match and a really good friendly friendly for us.
"I don’t know how the Celtic lads would have felt about playing it because if we had played our first league game on Saturday and had another one on Saturday it wouldn’t be the ideal preparation, but they came here and put on a good show."
Teddy Sheringham has revealed that 'a few harsh words' from Glenn Hoddle helped kick the lads into gear against Celtic on Wednesday night.