Robin van Persie's late curler ended the Baggies mini-Christmas revival after Gareth McAuley's early own goal.
"There was a stage in second half when we had a really good control. I thought the game was more likely to go 1-1 than 2-0," said Clarke.
"Ben Foster made some good saves, that's why we spent our whole transfer budget on Ben in the summer.
"Some of the football we played was very good and I thought the goal would come. We had players on the pitch who can score and got into some good positions."
"The fact they had to bring some of their big guns off the bench shows how well we were doing.
"In the first we were too timid. We spoke at half-time about being too respectful and in the end, the scoreline doesn't reflect the way we played."