However, United pulled out of talks with Chelsea due to the loan fee and the inability to include a break clause as part of the deal.
United confirmed their loan deal to sign Reguilon on Friday but Neville was surprised his former club moved for the Tottenham left-back.
‘I have to say I was a little bit surprised that we were going for Reguilon,’ Neville told Sky Sports.
‘Obviously, we’ve got the issue with Luke Shaw which means it is a stop-gap, it is a temporary measure. They’ve left themselves short in that position.’
Amrabat, meanwhile, travelled to Manchester on Friday after United agreed a £7.5 million loan deal which can be made permanent for £17.5m next summer.
Neville has questioned why United have left it late to make a move for the Morocco international but insists the midfielder is set to become a key part of Erik ten Hag’s plans at Old Trafford.
‘I don’t think the Amrabat one is a panic, because I think they’ve wanted him from day one.
‘I think he’s wanted that ball-playing midfield player, go back 12 months to Frenkie de Jong.
‘Mason Mount isn’t a ball-playing midfield player, he’s more if you like… I think he presses well, I think he links well, I think he runs forward.
‘I think he [Ten Hag] has always wanted this type of player. So I don’t think this is a panic, I think it’s always been Erik ten Hag’s want, a player like this.
‘I just don’t know why it hasn’t happened earlier. Obviously the other signings were brought in earlier in the summer. There has been an issue with United getting players out, which has caused United a problem, maybe it’s that.
‘But I think with the way the season has started, the performance levels have been poor, I know they’ve picked up six points but that could’ve been a lot less than six points, the Wolves and Forest games they were very fortunate in.
‘So I think they have to react. They have to get someone in before the window [closes] because that midfield is a massive problem.
‘I don’t think it’s a panic, the Reguilon one is definitely a reaction to the situation that’s occurred, which is more of a panic.
‘You’ll know from what I said three weeks ago that Mount, Hojlund and Onana signings hadn’t made Manchester United any better, if anything it maintained where they are at.
‘I think from what we’ve seen the first couple of weeks it’s a little bit worrying because the performance levels have been well below what I’d expect.
‘They’re nowhere near Manchester City, that’s a fact, I don’t think any United fan is thinking that but what we would’ve wanted is to get closer to Arsenal, make sure we stay above Chelsea and Liverpool.
‘That’s the issue at the moment – Liverpool and Chelsea, and the other clubs, Newcastle and Aston Villa, are we as strong as them? I think we will get better, there’s a lot of experience in there, but I’m a little more worried than I was a few weeks ago, but I never bought into this idea that we were better.’
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