An unfortunate 32nd minute own goal from young defender Darnell Johnson was all that separated the two sides in Hertfordshire during a lively, hotly-contested encounter.
City started with the same vibrancy of Monday’s 3-1 victory over West Ham United and they could have taken the lead after just six minutes at the home of Borehamwood FC.
Connor Wood’s searching corner fell perfectly for midfielder George Thomas on the edge of the Gunners penalty area, but his volley fizzled inches wide of the far post.
After 12 minutes, Josh Eppiah did brilliantly to muscle his way beyond Calum Chambers to latch onto Layton Ndukwu’s through ball before poking a hopeful effort beyond the corner.
It took Steve Gatting’s hosts until the 20th minute to worry Daniel Iversen in the City net, although Jeff Reine-Adelaide’s shot bobbled the wrong side of the near post.
Despite an encouraging start from City, it was the Gunners who opened the scoring when a dangerous cross from Jordi Osei-Tutu deflected into Iversen’s net off Johnson’s knee.
Arsenal almost doubled their lead before the break as Eddie Nketiah, who scored a hat-trick in this fixture last term, forced Iversen into an acrobatic save from 30 yards.
When Ndukwu’s corner came to Josh Gordon in the box, the striker showed his battling nature by scooping the ball up and working a goal-scoring opportunity from nothing.
The 22-year-old’s drive towards the bottom post, though, was knocked wide by Josh De Silva.
After the break, the Foxes introduced Admiral Muskwe to the action, with the 2016/17 top scorer replacing Josh Eppiah alongside Gordon and Ndukwu in attack.
City carried the greater threat straight after the restart but Nketiah and Reiss Nelson went close for the hosts with efforts from long range.
When Leicester ventured forward, they more often than not had Arsenal worried. Wood’s deliveries were proving key but, on the hour-mark, Sam Hughes couldn’t pick his spot.
The visitors really tested Arsenal as the clock ticked down with Liandro Martis volleying wide seconds after fellow substitute Kiernan Dewsbury-Hall was denied by ‘keeper Matt Macey.
Defender Josh Knight, too, was denied late on by Macey as the hosts stood firm. In the end, the Foxes can ultimately be proud of their performance, if not the result.
Key moment
It was a moment which summed up City’s lack of good fortune in Herfordshire.
For all of their endeavour in the latter stages, they just could not plot a route past the Gunners defence and Johnson’s own goal ended up being the difference between the two sides.
Who impressed?
After playing alongside Nigerian international Kelechi Iheanacho four days previously, striker Gordon was an impressive figure yet again for the Under-23s.
Hamza Choudhury, too, was a calming presence for his team-mates in the middle of the park, something Steve Beaglehole will have be pleased to see from his skipper.
Where do we stand?
City remain in fifth place with seven points to their name after five matches, although they are likely to fall when their PL2 rivals contest fixtures over the weekend.
Coming up…
Leicester have seven days to prepare for their next outing, the visit of Chelsea to Holmes Park next Friday (7:05pm kick-off).
You can watch that fixture, City’s sixth of the new PL2 season, live and free from 15 minutes before kick-off on LCFC TV.
The details…
Arsenal: Macey, Osei Tutu, Da Silva, McGuane, Chambers (Dragomir 73), Pleguzuelo (c) (Bola 63), Nketiah, Willock, Akpom, Reine, Nelson.
Subs not used: Gilmour, Iliev, Fortune.
Goal: Johnson OG 32’.
City: Iversen, Pascanu (Martis 74), Wood, Hughes, Knight, Johnson, Thomas, Choudhury (c), Gordon, Ndukwu (Dewsbury-Hall 64), Eppiah (Muskwe 45).
Subs not used: Bramley, Kaba Sherif.