Despite travelling to the South-West with the rest of the Boro squad on Sunday, O'Neil did not even make the 18-man squad that secured the club's first win in three matches.
The midfielder has made 99 appearances for the Teessiders, and the 100th will trigger a £1m payment to his former club, Portsmouth.
As a result, Strachan met with chief exceutive Keith Lamb and agreed not to play O'Neil, who is expected to leave the Riverside this summer despite signing a oneyear contract extension earlier this season.
With the administrator in charge of Portsmouth refusing to renegotiate the terms of the £4m deal that originally took O'Neil to Teesside in 2007, it seems extremely unlikely that the 26-year-old will play in the final four games of the season, but Strachan insists the situation will be assessed on a match-bymatch basis.
I think the situation with Gary was widely reported over the weekend, said the Boro boss, who watched goals from Stephen McManus and Jonathan Franks secure a deserved win. There we go, that's what's happened.
I deal with the footballing side of things, and other people take care of the financial side of it.
Then, we get together, discuss it, and this was the best decision to come out of that discussion.
What happens in the future depends on whether the circumstances change. We need to take each game as it comes now.
Strachan would be much more likely to push for O'Neil's inclusion if Boro were in a better position in the table.
Yesterday's win might have extended the club's unbeaten run to seven games, but with Swansea, Leicester and Blackpool all winning, the gap to the final play-off place remains a hefty six points.
The gap looks all but insurmountable with just four games to play, but things might have been different had a number of recent drawn matches ended in the same result as yesterday's game.
We've had opportunities to win a lot of the games that we've drawn, but we've not taken them, admitted Strachan.
There have been a lot of matches a bit like this, but we haven't taken our chances so we haven't won the game.
The difference here was that we scored with a couple of the chances that came our way.
It was a smashing victory.
It was never going to be a game where you saw terrific football, but I thought we put a few decent passes together at times and a lot of our play wasn't too bad.
Boro were also indebted to goalkeeper Brad Jones, who saved Alan Judge's first-half penalty after Justin Hoyte had been penalised for handball.
It's nice of us to get a bit of a break, but a penalty save isn't about luck, it's about ability, said Strachan.
Source: Northern Echo
Source: Northern Echo