The Ecuadorean quickly drove forward and exchanged passes with Paul Pogba.
By the half-hour mark, Arsenal were by far the dominant side and it was only due to the brilliance of de Gea in goal and Nemanja Matic around the penalty box that United somehow survived a Gunners onslaught till half-time.
Valencia struck a low shot that went in between goalkeeper Petr Cech's legs in the fourth minute.
Anthony Martial flicked on to Lingard in the area and the latter's effort careened in off a post.
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That draft code will not be available until September 2018 at the earliest, Education Secretary John Swinney has said. The Scottish Conservative leader branded the policy a "mess" at First Minister's Questions on Thursday.
Midfielder Aaron Ramsey was onside when he touched the ball back to Lacazette who fired it past De Gea.
But it was the Spaniard's quick reflexes that kept his team in the match, especially when he denied Arsenal an equaliser with a double save in the 57th from Lacazette and Alexis Sanchez.
Manchester United were taking on an Arsenal side following 13 successive Premier League victories at The Emirates to give Arsene Wenger's side confidence ahead of the visit of their bitter rivals.
Global gold prices almost unchanged as dollar holds firm
Among other precious metals, silver fell 0.4pc to $16 an ounce, after hitting its lowest since mid-July in the previous session. Gold prices were mostly steady on Thursday amid a firm dollar, trading within sight of a two-month low hit earlier this week.
Paul Pogba was sent off in the 74th minute for a challenge on Héctor Bellerín, and will now miss the all-important game against Manchester City next week.
Arsenal had two genuine penalty shouts waved away in the closing stages with de Gea nearly singlehandedly keeping the Gunners at bay with some incredible saves.
Arsenal had 33 shots on goal, with 15 on target, while United had eight shots with four on target.
However, despite the red card, Pogba's performance had clearly made enough of an impression on his compatriot and Arsenal icon Thierry Henry, who was pictured at the Emirates Stadium after the game chatting to Pogba and Jose Mourinho alongside William Gallas and fellow Arsenal legend Robert Pires.
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They expect this year's earnings to fall -44.44% year-over-year to -$0.15, followed by -113.33% decline in the next year to $0.02. California Pub Employees Retirement Systems has invested 0.16% of its portfolio in The Charles Schwab Corporation (NYSE: SCHW ).
Arsenal now sit in fifth place and are 12 points adrift of leaders Manchester City, who have a game-in-hand over the Gunners.