Lukaku nodded home Goran Popov's cross to give the Baggies a 2-1 win for his sixth goal of the campaign and Clarke was full of praise for the former Anderlecht man who has continued to impress despite being second choice to leading scorer Shane Long this term.
"Romelu has done well, he is a big talent, he has got a big future ahead of him in the game," he said.
"The fact he couldn't get in the team for most of the season is down to the form of Shane Long who shouldn't be forgotten today.
"Shane made a difference when he came onto the pitch, he tied up the other centre-back, has given a bit more space to Romelu, and maybe that's why he has got the space for the winning goal.
"It's a team effort and we don't like to single out individuals."
Clarke added that he was unsure if Chelsea would recall Lukaku in the January transfer window.
"He is on a season-long loan but there is an opportunity for the parent club to take him back in January. I can't affect it so I don't like to talk about it," he said.