The 43-year-old was an attendee at the sold-out Memorial Stadium on Saturday as he saw the Gas come from a goal down to claim another home win in their pursuit of promotion.
Rather than spend a weekend away from football, he casted an eye on potential transfer targets for next summer with the Hampshire side likely to be in the third tier next season.
“It’s for us to watch football, we always enjoy going to watch football in divisions which are not your own,” said Cowley to The Portsmouth.
“We’ve watched loads and loads in League One, we’ve got a really good handle on that. ‘But it’s an opportunity for us to watch League Two games.
“For us, there’s a number of out-of-contract players we need to be aware of.
“There’s some good, young players we’d really like.”
Cowley has previously worked with Rovers winger Harry Anderson at Lincoln City, with the tricky winger playing 141 times under the former Imps boss.
Anderson, 25, is contracted to the club until the end of the 2022/23 season, so he will be at the club no matter what division they find themselves in unless a transfer offer comes in for him.
Cowley could have been casting an eye over the likes of Sam Nicholson, whilst there may have been an outside chance of Antony Evans playing.
Evans was ruled out by Barton in his pre-match conference but the Portsmouth boss may have attended to see whether he was calling his bluff or getting a feel for the player.
The 23-year-old is available on a free transfer in the summer, and has been one of the most best performing players with eight goals and eight assists.
Portsmouth have a model of signing players from a lower level, before working with them and making money from them, so Evans fits the bill.
But that is not to say that some of Rovers players who have their futures secured are not potential targets to the two-time FA Cup winners either.
“A lot of the good, young players who are good enough to play for Portsmouth are ultimately in contract,” Cowley said.
“If they are not in contract, they will have compensation around them. ‘It’s our job to be aware of them, if they are affordable to us is another question.
“We also certainly have to be aware of the out-of-contract players because we have a lot of work to do in the summer.
“If they are above 24 and they are out of contract they will become free agents.
“But we’re also realistic to know there aren’t too many free agents in the lower leagues who are ready to come to Portsmouth and achieve what we want to achieve as a club.”
As well as attending Rovers match, he attended Northampton’s 2-0 win over Hartlepool United during the international break.
One player that he earmarked from the Cobblers was former Rovers left-back Ali Koiki, who was injured when he attended.
Though he ruled out any possible move for the 22-year-old, despite him being available on a free in the summer.
“The left-back (Koiki) was injured. He’s an athletic, powerful boy - but we’ve obviously got Denver (Hume), young Liam Vincent and Connor Ogilvie who can play that position. ‘It’s probably not an area we’re looking to add to.”