Dominik Szoboszlai, Mohamed Salah and Cody Gakpo (two) scored for the hosts, before Jacob Greaves headed home a late consolation.
“A difficult game, a difficult position to be in at half-time, but also a frustrating position because in some aspects similar to last week in terms of there being some positives in the first half,” McKenna said.
“It didn’t feel like we were under huge pressure. We started the game well and from very, very little, from not a huge amount of pressure we found ourselves behind in the game and then a few goals behind in the game. Liverpool executed well and we didn’t defend our box well enough.
“So we found ourselves in a really difficult position in the game, especially after last week, a really difficult game management scenario, and I think we can take a lot of positives from the second half.
“Firstly, in terms of the early stages of the second half, everybody stuck together, we learned some lessons from last week, we stayed in our organisation, we managed the game pretty well.
“We still showed some good passages and moves with the ball as well and then we finished the game really strongly. The subs came on, had a really good impact, we got a goal back, we could have had another goal and the fans got some reward in terms of a goal in front of them.
“It’s a difficult game on top of a difficult game last week. We’ve made some mistakes in there that we can learn from, there’s reasons for that as well.
“But I feel like it’s one that if we take the lessons in the right way, and now we get to work hard on it, that we can be stronger for.
“I think finishing the game in the manner that we did at the end of two difficult games is a big positive and a good sign for us.”