Benson's injury-time header settled a dour game in the Robins' favour, lifting them back into the top three and earning them their first ever win over Chesterfield at the 12th attempt.
Yates said: "That was a big win for us and we showed a bit of character. It was a tough game and the pitch affects us as we want to play football and it was bobbly out there and lively.
"But credit to the players because we stuck at it and we had talked about getting two wins on the bounce, which we haven't had for a while. We kept going and we kept going and we got our rewards. The game never got going, but that could be a massive three points for us come the end of the season.
"We have to create more chances for Paul Benson because he will take them. The lads have done what I asked and it was about getting the job done.
"They made it hard for us and the big lad up front (Armand Gnanduillet) was a handful and our defenders knew they'd been in a game. Paul Cook has a good squad and I like a lot of their players."
Cook admitted his team must address their lack of goals as their play-off hopes suffered another blow at the Abbey Business Stadium.
"That was disappointing and was the goal their first shot on target in the 91st minute? I think so," Cook said. "We aren't scoring and it's hard for us. We are trying all sorts of different things but we have to keep working.
"It's football and I can have no criticisms over the performance and I have no problem if we work as hard as that, but we shouldn't have lost the game. Our perennial problem is not scoring, but when you know your problems it's a good thing and we couldn't quite solve that.
"Cheltenham are a very strong side and they are no mugs, but we played better than the we did in our win at Dagenham on Saturday and I think the lads are getting used to each other. It's getting more and more difficult to get into the play-offs for us."