Cambridge striker Daniel Chillingworth is ending his season on a high note after suffering the misery of being sidelined for seven months by injury.
He scored twice for the second match in succession to help ensure his side's league status after their shaky campaign.
Cambridge took a grip on a nervy encounter between two sides who showed exactly why they were in relegation trouble by hitting two goals in a minute late in the first half.
Ashley Nicholls won a race with goalkeeper Tom Evans to prod the ball home in the 37th minute, and with the Scunthorpe defence still disorganised after the restart Chillingworth expertly controlled a Shane Tudor cross to curl a shot in from 12 yards.
Blasted by manager Brian Laws, Scunthorpe made a spirited start to the second half but needed a freak goal to put themselves back in contention.
Veteran Peter Beagrie floated the ball in directly from a corner kick, over the outstretched hand of goalkeeper Shaun Marshall.
But Cambridge were always the better team and quickly restored their two-goal lead in the 76th minute when Chillingworth headed home after Danny Webb's header rebounded from the crossbar.
Steve Torpey's stoppage time second for Scunthorpe was virtually irrelevant, especially after the news that Cheltenham's equaliser at Carlisle guaranteed both teams would stay up. But neither manager could say he would be in charge next season.
Cambridge's Claude Le Roy commented: "In the few weeks I have been at Cambridge I have had a strong feeling for the club and the supporters, and the players have responded brilliantly.
"But at the moment I have several other offers, some from international set-ups which I owe it to my family to take into consideration." Brian Laws, recalled by Scunthorpe after being sacked last month, disclosed he was still applying for other jobs.
He said: "I just don't know what the situation is at the moment. It's a great relief that we've managed to stay up, and what I do know is that we mustn't put Scunthorpe Football Club in this situation ever again.
More has gone on in the last couple of months than would happen at many clubs in 20 years."