Cobblers boss Jimmy Floyd Hasselbaink was disappointed as he reflected on the Boxing Day game at Doncaster.
“We were very flat,” he said.
“The intensity wasn’t there, we were fired up before the match but we gave Doncaster a bit too much respect and I’m very disappointed.
“At 1-0 we had a good chance to make it 1-1 and then straight away they go up the other end and it’s 2-0.
“I didn’t think it was a penalty but even before that we weren’t good enough.
“Maybe I got the team selection wrong and I will look at that but the intensity just wasn’t there from us today.
“We are still too much up and down in our performances and that needs to change.”