He said: "He did well to get the ball and he has got to learn to pass the ball and to concentrate more.
"I'm disappointed that we have lost his services for the next match."
The winner came nine minutes into the second half when unmarked Emil Hallfredsson raced into the penalty area and fired home from 12 yards.
Watford could have levelled in the fifth minute of stoppage-time as Henri Lansbury's free-kick from 28 yards was heading towards the back of the net before goalkeeper Luke Steele turned the ball round the post.
Robins reserved special praise for the former Manchester United reserve.
He added: "He hasn't had a lot to do but he has made a world-class save and earned us the three points today."
Assessing the goal, Robins said: "He (Hallfredsson) got behind the full-back and got in a great position and stuck it in the net."
Watford had reason to feel aggrieved after seeing a goal disallowed for pushing in the Barnsley box.
Robins admitted the decision was somewhat harsh, saying: "I thought we were fortunate that the ref disallowed it."
Watford boss Malky Mackay felt his team were more than worthy of a point and slammed the referee's verdict on the goal which was scratched off.
He said: "I've looked at it on video five or six times and there was no push by Danny Graham. It was clear that he headed the ball and there was no pushing.
"I thought we deserved more than we got out of the game. We picked up from where we left off against Sheffield United.
"I was pleased with the side's performance. I thought we gave a good account of ourselves. We knew it was going to be a tough game."