Bruno Fernandes, Daniel James and Victor Lindelof were also on target for the Red Devils, who climbed to third in the Premier League table following the emphatic victory.
Maguire was delighted with Manchester United’s performance against Leeds and reserved special praise for ‘magnificent’ McTominay.
He told the club’s website: ‘You’ve seen in recent months how we’ve been relying on the forward lads in Rash and Bruno, so for Scott to score was great.
‘He was magnificent – one of the best performances I’ve seen and played with on the pitch from a central midfielder.
‘He deserved his two goals and it’s nice for Victor to get on the scoresheet as well, it’s something we’ve worked on – a great touch from Anto at the front post.
‘It’s nice to spread the goals around, we know we’ve got goals in the team and it was a great night for players to get on the scoresheet.
‘But more importantly everyone is happy with the performance, the six goals and the three points.’
Manchester United are just five points behind Premier League leaders Liverpool and could close the gap further when they play their game in hand.
But Maguire insists his team-mates are not getting carried away by talk of a title charge and are purely focused on their next fixture.
He added: ‘I think it’s just important to keep winning games and looking after your own points tally.
‘You can get ahead of yourself in terms of looking at other people’s results and you just need to look after yourself. If you keep winning games and putting three points on the table then you’ll be there or thereabouts.
‘We’re not getting carried as I said. We had a big win [against Leeds] but there is lots of improvement we need to make to make sure we’re challenging at the end of the season. That’s what we’ve got to aim for.
‘It’s so open this year. We tend not to look at the table – I couldn’t tell you now where we’re sat in the table. We take each game as it comes.
‘Sometimes it’s the performance you have to look after because your performance over the season will eventually get the points that it deserves.
‘It’s still early on in the season. I think after three or four games you saw people speaking about how bad our start was and now you hear people saying we’re title challengers. That’s football.
‘We’ve got to deal with that, stick to what we’re doing and keep improving on the training pitch and on the pitch, and see where it takes us.
‘For sure, it was a great win for us against Leeds, but we’ve got another great game coming up and one we’re looking forward to.’