English Premier League teams Bournemouth, West Bromwich Albion and Stoke City all bowed out.
England and Manchester United legend Sir Bobby Charlton has been Manchester United's all time highest goalscorer since almost a quarter of a century.
Martial showed good feet to breeze past Chris Gunter and pick out Mata, who teed up Rooney to divert the ball into the far corner for his record-equalling goal on seven minutes with his 249th for Man Utd, level with leading scorer Sir Bobby Charlton.
"United look like they've got goals everywhere at this moment in time", he told BT Sport.
Reading are playing well under Jaap Stam - they're now third in the Championship - but were unable to resist Jose Mourinho's side on Saturday afternoon.
But he has lost his place in United's starting XI following Mourinho's arrival as manager and has had to make do with occasional starts in the cup competitions of late.
Rooney has won the Champions League, five Premier Leagues, the Club World Cup, two League Cups and the FA Cup at United over the past 13 years.
Charlton, who came up through the United youth system, spent 17 years at Old Trafford before finishing his career with spells at Preston and Irish side Waterford United.
It was a flying start from United and they could have gone in front twice in the opening two minutes; Rashford flashing a shot wide from the edge of the box before Ali Al-Habsi got down well to keep out Rooney's left-footed effort.
Rooney's first chance to break the record will come, if selected, against Hull City in the first leg of the League Cup semi-finals at Old Trafford on Tuesday.
Four more EPL teams face FA Cup action on Monday (NZ Time). "I am delighted because I know what defeating Bournemouth means to our fans".
The footage was widely circulated across social media after the game, with City supporters taking great delight in Evans' supposed snub.
It could have been more "We played well and, without Zlatan [Ibrahimovic] today, we had to go for a different style of play and Marcus [Rashford] is very fast in getting behind people".