These two teams met in last season's play-off semi-final but both clubs have fallen well short this time.
Cobblers lost at Rochdale in midweek but earned a point when Lee Norris cancelled out Byron Harrison's opener to deny Cheltenham back-to-backs wins after the Robins saw off Morecambe on Tuesday.
Yates said: "I thought we were brilliant, it was one of our better performances. But the lesson to take from the game is that when we're on top we need to kill teams off.
"We were dominant in the first half but were only playing at 70 per cent. We've had enough chances to win two games, we've had several good ones in the second half, and I can only remember Northampton having one shot on target.
"I'm disappointed we haven't won but we played some good football and showed a lot of quality. We've taken something from the game, which was important, but it should have been more.
"Northampton hardly got the ball into our box before they equalised and it came at a bad time just before the break. But, if anything, we stepped it up in the second half and the game became more open.
"Northampton had to change their shape to cope with us but we still created some good chances, we did everything but get that second goal to win the game.
"At times it was almost too easy for us - and I don't mean that disrespectfully - but we were coasting without killing the game off. I felt there was more to come from us but we didn't take the game by the scruff of the neck, it was too comfortable for us at times."
Cobblers boss Aidy Boothroyd said: "We didn't play very well, we showed flashes of things but nowhere near enough and the first half was poor.
"We relied on a fumble from them, an error that we forced them into, for our goal but you couldn't ever really say we deserved to be in front in the game.
"It wasn't great but we'll play worse than that and win, we're digging out results at the moment but I'm sure we'll start creating chances soon.
"We found a way to snatch defeat from the jaws of victory on Tuesday at Rochdale and today we've managed to get back into the game after not playing very well. Clearly there is still work to do but slowly we're getting there and a point today is another one on the table."