Arsenal's English midfielder Theo Walcott (R) watches his shot as he scores their second goal, his 100th goal for Arsenal, during the English FA Cup fifth round football match between Sutton United and Arsenal on February 20, 2017Arsenal's English midfielder Theo Walcott (R) watches his shot as he scores their second goal, his 100th goal for Arsenal, during the English FA Cup fifth round football match between Sutton United and Arsenal on February 20, 2017 (AFP Photo/Glyn KIRK)
The England forward added to Lucas Perez's opener as Arsenal returned to winning ways following their 5-1 drubbing by Bayern Munich last week and set up a home quarter-final with another non-league team, Lincoln City.
But the narrow margin of victory belied the 105 places that separate the two teams in England's football pyramid, with Sutton currently 17th in the fifth-tier National League.
"We did the job," Arsenal manager Wenger told BBC Sport.
"It was not an easy game at all. We have to give them credit because every error we made they took advantage of on this pitch. They played very well."
South London club Sutton had hoped to emulate their famous 1989 win over Coventry City, FA Cup winners 19 months previously, but there was no disgrace in defeat in their first ever fifth-round game.
Arsenal were given several uncomfortable moments on the 3G pitch at Sutton's 5,000-capacity Gander Green Lane ground, which was full to bursting with fans in yellow Sutton T-shirts, hats and scarves.
The home supporters almost had a goal to cheer as well, but Roarie Deacon, who began his career at Arsenal, saw his 25-yard effort cannon back off the bar in the second half.
"It was a dream to watch my team play against Arsenal. I'm very, very proud," said Sutton manager Paul Doswell.
"This was our cup final and these players will go down in history at the end of the day."
Wenger will continue to face questions about his future but, for now at least, his dream of winning a record seventh FA Cup remains intact.
- Holding careless -
For all the international players in Arsenal's ranks, there was no distinct gap in quality between the sides in the early exchanges as the visitors slowly got to grips with the unfamiliar surface.
Arsenal's first shot, a Mohamed Elneny effort that sailed miles off-target, drew hoots of derision from the home fans, but in the 26th minute the visitors went ahead.
Perez swapped passes with Xhaka and then cut in onto his left foot from the right flank before sending in a skidding low cross that evaded everyone to nestle in the bottom-left corner.
Briefly, Arsenal threatened to make their experience count, with Nacho Monreal drawing a smothering save from Sutton goalkeeper Ross Worner and both Walcott and Alex Iwobi going close.
But Arsenal's over-confidence at the back twice almost gifted Sutton an equaliser.
Rob Holding nearly had his pocket picked on the edge of his own box and shortly before half-time Ospina passed the ball straight to Sutton's Adam May, who fired wide with his left foot.
An overhit Holding back-pass that sent Ospina scrambling had Arsenal's fans holding their breath again within seconds of kick-off in the second half.
They gave themselves breathing space in the 55th minute, however, when Monreal crossed low from the left and Walcott turned in his milestone goal from close range.
But if Arsenal thought their second goal would put the game to bed, they were mistaken as Sutton produced their best spell of the game.
Maxime Biamou shot straight at Ospina, captain Jamie Collins powered a header over the bar at a corner and Deacon, the ex-Arsenal trainee, cracked a shot against the crossbar from distance.
The closing stages yielded the surreal sight of Arsenal's Chilean star Alexis Sanchez, one of the world's most feared forwards, making his entrance as a replacement for Iwobi.
"Who are ya?" chanted Sutton's fans, their sense of mischief intact until the end.