Several players from United's first-choice starting line-up, including Paul Pogba, Romelu Lukaku and Jesse Lingard, are resting after the World Cup and could miss the opening league fixture against Leicester City in less than two weeks' time.
Morata, who had scored his first goal for the club in last week's 2-0 win over Villarreal, rose to head home from close range on the half-hour mark following a corner which had been flicked on by Atleti captain Diego Godin.
Indian football was a picture of good health with a 10-man under-20 outfit's triumph over Argentina
Following public comments from La Liga chief Javier Tebas, who said it was "not ideal" for the second El Clasico meeting between Real and Barca last season to be played with the latter having already won the league title, the two sides will face off earlier this campaign.
Sevilla became surprise Liga leaders on Sunday after beating visiting Celta Viga 2-1 while champions Barcelona drew 1-1 at Valencia thanks to another Lionel Messi strike but are still without a victory in their last four league games.
Images from the English Premier League matches played on Tuesday
Unseeded Russian Mikhail Youzhny denied top seed and defending champion David Ferrer a fourth Valencia Open title when he beat the world number three 6-3, 7-5 in the final of the Spaniard's home event on Sunday.
World No. 3 David Ferrer has reached the semi-finals of the Valencia Open for the fourth consecutive year with a 6-4, 4-6, 6-0 win over fifth seed Jerzy Janowicz.
Arsenal's Pierre-Emerick Aubameyang struck a vital late goal to seal a 3-1 win over Valencia on Thursday and give his side breathing space for the second leg of their Europa League semi-final in Spain next week.
Public buses have gradually disappeared due to scarce or prohibitively expensive tires, motor oil, batteries and spare parts.
A round of Wednesday night's Champions League group stage matches.
Jose Mourinho was adamant on Friday that his relationship with Paul Pogba is "good" and said that the Frenchman would play in Manchester United's English Premier League match at West Ham United on Saturday.
News of all that's transpired on and off the football field
News of all that's transpired on and off the football field
Barcelona's 100 per cent start to the season was ended by Catalonian neighbours Girona, who picked up a draw at the Nou Camp, allowing Real Madrid to take advantage with a victory over Espanyol.
Karim Benzema netted a second-half hat-trick as Real Madrid got back to winning ways with a 3-0 victory over Athletic Bilbao in La Liga on Sunday.
Neymar made his return to the pitch after a three-month injury lay-off as Paris St Germain celebrated their eighth Ligue 1 title with a 3-1 win against Monaco at the Parc des Princes on Sunday.
Mourinho praises Pogba, Shaw, Dalot after United Swiss stroll
La Liga leaders Barcelona handed Real Madrid more hope in the title race as they drew 0-0 at Athletic Bilbao on Sunday, only avoiding defeat thanks to some outstanding saves by Marc-Andre ter Stegen.
The Portuguese can expect a hostile reception in Valencia, who had to suffer 15 of his goals for Real Madrid and are returning to the Champions League for the first time in three years.
Carlos Vela helped Real Sociedad overcome a European hangover when he grabbed a second-half equaliser to earn a 1-1 draw at promoted Elche in La Liga on Saturday.
Summary of sports events and persons who made news on Friday
The 28-year-old striker, who scored 30 goals in 46 appearances for Valencia last season, is part of a growing number of Spain internationals who are leaving their homeland to play in the English Premier League.
Fernando Hierro now in charge of the team, Spain's next game is against Group B leaders Iran on Wednesday.
A round-up of Wednesday's night's UEFA Chmpions League matches.
Last season's runners-up Liverpool, big-spending French league champions Paris St Germain and Carlo Ancelotti's Napoli were thrown together in the pick of the groups while holders Real Madrid must face last season's semi-finalists AS Roma.
News of all that's transpired on and off the football field
Lucas Moura scored twice as Tottenham Hotspur romped to a 3-0 English Premier League win over Manchester United at Old Trafford on Monday as Jose Mourinho's team's defensive frailties were brutally exposed once again.
Barcelona suffered a first home defeat of the season when they lost 3-2 against Valencia after finishing with 10 men in La Liga on Saturday, leaving the door open for Madrid rivals Atletico and Real to move above them.
Chelsea's Marcos Alonso and Real Madrid's Nacho were notable absentees in defence, along with Atletico Madrid midfielder Koke.
La Liga leaders Barcelona hit two goals in the final three minutes to earn a 3-2 win at Rayo Vallecano
Valverde said he was concerned about the team's away form after they were comprehensively beaten 2-0 by promoted Granada
A summary of Saturday night's matches in the Euro 2020 qualifiers.
Images from the Champions League matches played across Europe on Tuesday
Valencia coach Ernesto Valverde has said the instability at the club has convinced him it is best to leave after they lost 4-3 at Sevilla on the final day of the La Liga season on Saturday and missed out on a Champions League place.
Unai Emery begins the task of steering Arsenal into a brave new post-Arsene Wenger world.
India stun Argentina in U-20 COTIF Cup football tourney
Summary of sports events and persons who made news on Monday
Sergio Ramos equalled Iker Casillas's record of 167 appearances for Spain on an emotional night at Sporting Gijon's El Molinon stadium, which paid tribute to the late Spain and Sporting forward Quini before kickoff.
'We are like his home. We are like his family ... We are going to help him to feel good'