Thurston was expected to return from two shoulder reconstructions in round five and was only cleared for full contact training earlier this week.
However, the two-time Dally M medal winner marked a remarkable return more than four weeks earlier than expected when he led the Cowboys out against the Titans on the Gold Coast.
Thurston said he sought out specialist help to combat his self-doubt.
"(I was) very nervous coming back from two shoulder reconstructions and there's also a bit of doubt in your mind," he said.
"I did some work with a sport psychologist over the last few weeks and got me head right. (sic).
"(I've) beat those demons I think."
Cowboys coach Graham Murray didn't have to wait long for Thurston's shoulders to be tested - he was involved in the first tackle of the match on Gold Coast prop Michael Hodgson.
"Muz (Murray) said to me not to hide on the wing there for the first set ... and once I got the first tackle, my shoulders pretty much went out the back (of my mind) and I was ready to go," Thurston said.
Thurston tried to carry the Cowboys on his reconstructed shoulders, scoring all but four of the Cowboys points, including two tries.
It wasn't enough, but Murray expected Thurston to gain confidence from the impressive hit-out.
Murray said the final decision on Thurston playing was left with the Cowboys skipper.
"He's as strong as he's ever been, he's stronger than he was last year so the basic principle was his confidence in (himself)," Murray said.
"To his credit, he's a tough bloke he's come back, he played all last season with bung shoulders and now he's back.
Every day he got more and more confident and each day he'd test the coaching staff."