Manchester United produced a vital victory in the Champions League on Wednesday night.

The Red Devils came from behind to score a 2-1 triumph at Old Trafford to open their account in Group B after an opening day loss to PSV Eindhoven.

It was a must-win game for Louis van Gaal's United and the players were aware of the magnitude of the match, as evidenced by their reactions on Twitter.

Love @ChampionsLeague nights and they're even better with a win! Great result...Next stop Arsenal! @ManUtd#MUFCpic.twitter.com/EIYFIz2RnI
— Phil Jones (@PhilJones4) September 30, 2015

That was a special night... Atmosphere at Old Trafford something different.. Well done boys! @ManUtd#ChampionsLeaguepic.twitter.com/QY4yZ8azM6
— Juan Mata García (@juanmata8) September 30, 2015

What a feeling!! @ChampionsLeague nights are special! @ManUtd@Memphispic.twitter.com/ltU8cWnmON
— Chris Smalling (@ChrisSmalling) September 30, 2015

Great result and team spirit!! Amazing atmosphere in the stadium thanks! #MUFC#CLpic.twitter.com/OwPQL8SddG
— Daley Blind (@BlindDaley) September 30, 2015

Good Win tonight thanks for you support https://t.co/iZ6mCjkTyt
— Anthony Martial (@AnthonyMartial) September 30, 2015

First-placed United will now focus their attention on Saturday's Premier League trip to rivals Arsenal.