Solanke struck twice after halftime to cancel out City's 2-0 lead before the break. However, he was clearly struggling late on.
Frank said afterwards: "He clearly struggled to run. So he knew, he struggled to run fitness-wise. We knew before the game again it would be a big push to play 90. He's not there fitness-wise where he should be, because he's been out for so long. And we've been, in a way, a little bit forced to play him.
"And I think it's pretty evident that he's relatively important for us. Four goals in four games, with him being on his 70-80% of fitness and top sharpness. But imagine City playing without Haaland for six months. So I think we've been quite hard-hit with injuries. Yeah, in general, but Dom was excellent.
"First one, I think there's clear contact from him on it. We want, in general, a higher threshold. I understand it's in the grey area. I think if the Liverpool goal, Ekitike, was in my opinion still, two clear hands in the back of Romero. So I think it's no grey areas.
"Very happy it finally dropped to us, which I think was more than fair. And the second one was something we, of course, trained yesterday, so it went well."
On the performance overall, Frank also declared: "I think I'm extremely happy that we finally got a point out of a big second half. And it felt like a big point, of course. Because we're playing against the best team in the Premier League in the last seven years, eight years. They're playing to compete for the title.
"And I said it before, this team's ability to respond to setbacks and show resilience, I think we are growing it bit by bit. And I think, and now it's game 11 since Nottingham Forest, where I think we are showing more consistency. We are more competitive. It's just going in the right direction."