Wayne Rooney has urged Manchester United to stop relying on Luke Shaw as a guaranteed starter, warning that the left-back's persistent fitness problems make him too much of a risk for any given season.

Speaking on his podcast, the Manchester United legend argued that the club must enter the transfer market specifically to address the depth issue at left-back — and he has a clear candidate in mind.

Lewis-Skelly the answer, says Rooney

Rooney pointed to Arsenal's Myles Lewis-Skelly as the ideal solution, describing the versatile youngster as an "absolute no-brainer" signing if the club can secure him at a reasonable fee.

"I think if you can get a player who can play left back, he can play centre midfield. He's young. He's got a massive future ahead of him. I think that's absolute no-brainer if you can bring him in," Rooney said.

The former England captain also referenced what he described as Shaw's underwhelming display against AC Milan, reinforcing his view that United cannot afford to build their defensive plans around the England international.

"I sort of think, if I'm Michael Carrick, I'm light at left back, I'm light in the midfield. So, I don't think you can rely on Luke Shaw to be consistent for the whole season," he added.

Carrick echoes the call for reinforcements

Rooney's concerns find support in Manchester United manager Michael Carrick's own public comments from last week. Carrick made clear that the squad requires further additions before the September 1 transfer deadline.

"We want more, we need more, we keep looking for how we can do that. Money's money, I get that. We feel like we have to be pushing for everything we're involved in, while being realistic of what the recent history's looked like over a period of time," Carrick said.

The manager struck a determined tone when pressed on the club's ambitions, insisting that every boundary must be tested in pursuit of winning.

"For now, we've got to make the most of it, but we've got to push every boundary we can to be able to win again, basically. That's the challenge," he added.

Manchester United have already been active in the window, with Barcelona completing a £65.4 million signing of Rodri from Manchester City among the headline moves reshaping squads across Europe ahead of the new campaign.