The former Republic of Ireland international was handed a new one-year deal by West Brom coach Clarke in the close-season despite being plagued by injuries last term.
Reid, 32, made his first top flight appearance of the season at Stamford Bridge last time out in the absence of the injured Billy Jones.
Clarke was delighted with the way Reid slotted into the side and believes the impact he also has off the field justified his new contact.
"It was good for Steven to get back into the team," said Clarke. "It shows that he's worked well.
"He hasn't had much chance to get back into the team because of the form of Billy Jones, but the way he's looked after himself is a credit to him because he came in and played 97 minutes no problem.
"I had a couple of good chats with Steven over the summer and, in my opinion, he made the right decision to carry on.
"He's got good attributes. I spoke about them last year - he's a 'man'. The more men you can have like that around your dressing room, the better.
"He's good around the place, even when he's not involved in the games. It's good to have him here.
"It's nice he got a chance to play - he showed he can still play a bit as well."
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