Sutton remain rooted to the bottom of League Two after Rob Apter’s late strike earned Tranmere a 1-0 victory.
Visiting keeper Steve Arnold produced a string of good saves, including saving a Connor Jennings penalty, to keep the home side at bay.
But there was nothing he could do to deny Apter stealing all three points at Prenton Park.
Sutton could have gone in front when Luke McGee parried Charlie Lakin’s cross to Harry Smith, who was unable to convert.
Arnold kept out Kieron Morris at the near post before a controversial moment saw Arnold push away an Apter strike before Joe Kizzi blocked Harvey Saunders’ strike on the line – with the hosts claiming Kizzi had used a hand.
McGee kept out Olly Sanderson before Arnold denied Apter and then Regan Hendry.
Saunders was fouled by Ryan Jackson in the box before Arnold thwarted the spot-kick.
Saunders saw an effort tipped over by Arnold, but Apter’s 20-yard strike eventually secured the win to leave Sutton six points adrift of safety.