Rooney struck either side of half-time at Old Trafford to give Giggs a victory in his first game as interim boss following David Moyes' sacking on Tuesday. The England striker's double was followed by a brace from substitute Juan Mata to seal United's biggest home league win of a miserable campaign.
Netherlands manager Louis Van Gaal and Real Madrid boss Carlo Ancelotti are among the experienced coaches reportedly being considered for the United post. But Giggs' decision to make six changes to the team beaten 2-0 at Everton in Moyes' last match seemed to revitalise United and Rooney insisted the 40-year-old Welshman would have no trouble taking over on a full-time basis despite his lack of managerial experience.
"Giggsy has come in, "Rooney told Sky Sports. "It was strange but we know he's a really experienced player and he's built to be a manager. We can see that as players, we can see how he's handled himself since he took over. Giggsy has got all the credentials to be the next boss but that decision is down to the board."
United legend Giggs, who had been working as a player-coach under Moyes, was given a warm welcome to the dug-out by fans who had grown disillusioned by the dour football and poor results served up by the Scot in his ill-fated ten-month reign.
United have slumped to seventh in the English Premier League table just 12 months after they were crowned English champions in the final season of Alex Ferguson's glorious reign. But Rooney, who was given a new contract by Moyes earlier this season, was adamant the players had to take a large share of the blame for the team's struggles.
"We're the ones on the pitch, we have to take a lot of responsibility (for Moyes leaving)," he said. "We've had a tough week and there's been a lot of negativity towards us as a team. We were hurt by that and we wanted to put that right. It's important for us to end the season well. We knew it was going to be a tough game, Norwich are fighting for survival. But thankfully we got four goals and a comfortable win."
Mata, who cost United a club record £37m in January, started on the bench after being dropped by Giggs. But the former Chelsea playmaker responded to claims that Moyes had lost the support of the players by insisting they had always given 100 per cent.
"The first half was difficult but in the second half we showed what Manchester United can do at home," he said. "We always try our best. Sometimes it's difficult to win, it's difficult to play. We didn't find enough space to create opportunities in the first half, but we're all together and our aim is to win the three games we have left."