The former world number one, who is easing his way back to full match fitness after a career-saving resurfacing procedure in January, saved all four break points he faced and dropped only six points on his first serve.
The club's hierarchy and recruitment under executive vice-chairman Ed Woodward has come in for severe criticism but Ole Gunnar Solskjaer has described that as 'an insult' as he looks to the future.
The Arsenal boss admitted that the car-jacking attempt targeting Ozil and teammate Sead Kolasinac in July had disturbed the midfielder's pre-season but said the former Real Madrid player was slowly winning his confidence back in training.
David De Gea pulled up with a muscle problem during Spain's 1-1 draw away to Sweden in qualifying for Euro 2020 on Tuesday and is expected to be sidelined for a few weeks.
Liverpool have won just five times at United in the Premier League era and the Red Devils have won the fixture 16 times, but the gulf in quality between the sides has widened significantly in recent years.
Stan Wawrinka has beaten Simon four times in seven meetings but the Frenchman prevailed in straight sets the last time they played each other on the hardcourts of Shanghai in 2016.