Nothern Ireland surely head into Euro 2016 as tournament favourites after beating Latvia 1-0 thanks to a Steven Davis goal.
A month after scoring twice against Greece to book his side a place at Euro 2016, Davis was back at Windsor Park to secure a deserved win.
Remarkably, they last won a non-competitive fixture in March 2008 – 23 games ago – and it has taken O’Neill 11 attempts to put an end to that sorry sequence.
Naturally, that pales in significance to his main achievement – a first major tournament appearance in 30 years – but it is yet another positive sign for a side who are building significant momentum.
Davis was once again the fitting figurehead, meeting Craig Cathcart’s fine cross with a parried header then following up from close-range in the 55th minute.
O’Neill took the opportunity to experiment with a 3-5-2 formation, his eyes clearly cast towards France and opponents stronger than the lowly Latvians.
Cathcart, Jonny Evans and Gareth McAuley offered a solid base at the back, though they were hardly tested by a passive opposition and Northern Ireland’s unbeaten run eased along to eight matches without drama.
With the home fans in fine voice as they toasted the team’s summer trip to France 2016, the impetus was squarely on the boys in green.
It became immediately apparent that left-back Antons Kurakins had been pinpointed as a weak link, with Conor McLaughlin given licence to attack the flank.
Jamie Ward, Davis and Oliver Norwood took it in turns to join him on the right, leaving Kurakins chasing shadows as the crosses poured in from his side.
None of them were finding their intended targets though and Andris Vanins’ first two saves came from a speculative Ward strike and a mis-kick from his own defender Vitalijs Makisimenko.
Vanins denied Ward a second time on the quarter-hour, Northern Ireland having carved open the Latvians with a patient passing move.
Kyle Lafferty and Stuart Dallas both played their part before Chris Baird found Ward with a clever ball over the top.
A rare foray forward from the away side drew a corner, with Olegs Laizans drilling a shot straight at Michael McGovern after meeting the initial clearance.
Northern Ireland upped the ante in response, Davis missing one promising opening then laying another on for Lafferty.
The Southampton midfielder could not quite get a full connection on his shot after good link play from Norwood and Dallas, leaving a simple gather.
Moments later he was back in the role of creator, springing a high line to set Lafferty free.
Having scored seven goals in Euro qualifying he would have fancied his chances of finishing the job but, after shaking off his marker, he pulled the shot wide across goal.
One more chance came and went before the break, Evans glancing past the post from a Norwood free-kick.
O’Neill made two half-time changes, Roy Carroll replacing McGovern and Corry Evans relieving Norwood.
Again, the hosts began brightly.
Lafferty accepted an invitation to cut into the box and take aim but his shot was parried firmly by Vanins.
It was Lafferty’s last major contribution, with Josh Magennis summoned from the bench after 54 minutes.
Seconds later they had the lead.
Cathcart launched a searching cross-field ball up the pitch, with Davis evading the attention of the Latvian defenders to arrive unmarked at the far post.
His header was blocked by Vanins but Davis had the presence of mind to follow up and sweep home from a yard.
Having scored twice in last month’s history-making win home win over Greece, Davis took his growing international tally to eight.
Liam Boyce and Shane Ferguson were given the last 20 minutes to impress as the changes continued, joined latterly by Paddy McCourt.
Ferguson was a lively presence on the left, and showed good resolve to pick Vladislavs Gabovs’ pocket on the byline, nearly forcing an own-goal.
Latvia almost kept the friendly curse going in the 87th minute, Artjoms Rudnevs hooking a shot tantalisingly close from 12 yards but the it would have been cruel on O’Neill’s men.