THE Dons seemed to have last year’s humiliating cup defeat by Siddall on their minds as they won in far from convincing fashion.
Conference leaders Thatto tried hard to inflict another third round Challenge Cup upset at the Keepmoat and they revived some bad memories when they scored first as winger Darren Woods caught a big kick to touchdown in the 2nd minute.
Shaun Quinn tagged on an 11th minute penalty to put the non-league side 6-0 up and it was not until the 20th minute that the Dons got back on level terms.
Jack Ely wriggled over the line from close range and then Stu Sanderson cleverly side-stepped an opponent seven minutes later, with Kyle Kesik adding a third Dons try in the 37th minute.
But Tony Miller’s men found it hard to shake off the visitors from Merseyside and another try from Woods cut the deficit to 18-12 at half time.
Former Dons man Woods completed his hat trick early in the second half to leave Thatto trailing by only two points before the home side reasserted themselves with tries from Mick Butterfield and Jamie Bovill in the 59th and 63rd minutes to seal a nervy win.
Thatto had the last word when Chris Frodsham touched down in the 66th minute to ensure Doncaster had to stay on their toes throughout the closing stages.