Admittedly, they should have finished their hosts off long before Doncaster were reduced to 14 men after lock Nick Civetta’s red card at the end of the first half.
Instead, though, Knights forged further ahead and Carnegie – who won late against Nottingham last week – were indebted to hooker Joe Buckle’s 81st-minute try improved by Alex Davies.
Lowes said: “I’m delighted with the result and a couple of wins over Christmas.
“They’ve not been great performances – we know all that – but you can handle that and train with that better off the back of a win.
“What I liked about this group of lads is never giving up.
“We went two scores down on the back of some poor stuff but we keep finding ways to get back against Nottingham and now Doncaster to win in the last minute. It’s a great mindset to have.”
Full-back Chris Elder was sin-binned but scored two tries while Andy Forsyth also crossed.
Carnegie move up to third and Lowes added: “There were some real basic errors but that’s a work in progress.
“These players are very committed to each other. That will never be an issue.
“But for us it’s some of our basic skills. We gave Doncaster too much field position and fair play to them they took their chances when offered.
“We need to stop offering them. But the pack was very good again, like against Nottingham, and it was an outstanding effort from our front-row.”