There may be a sense of what might have been for Blackburn Rovers at Deepdale but there should also be an acknowledgement that it could have been far worse too.

With a brimming away end expectant after an underwhelming performance against Birmingham City, Rovers needed a performance, as well as a result, to get buy-in from those hardened supporters.

It's very early in the John Eustace reign but building a connection between himself and the supporters will be vital over the next few months. Jon Dahl Tomasson did that in his debut campaign and it did buy him some patience from the fans.

Results are the primary focus for Eustace, he's made that abundantly clear, and there will be bumps along the road as he balances pragmatism with substance. Rovers fans, as with most supporters, will happily come along for the journey as long as there is a clear destination.

READ MORE: Eustace verdict as he highlights Rovers positives

From the first whistle, Rovers were far brighter. They harried and harassed Preston and carried a threat. The goals made it the perfect start, with Sam Szmodics and Sam Gallagher on the scoresheet.

In another world, Gallagher would've been hundreds of miles away in South Wales, lining up for Ipswich Town at Swansea. Rovers rejected the Tractor Boys' bids as they didn't meet the club's valuation.

With his contract up in the summer, though Rovers hold a 12-month option, there was reasonable debate in the fan base about what figure that should be. Gallagher is one of Rovers' highest earners and his injury record is chequered.

But after five months on the sidelines with a calf problem, Rovers' number nine has quickly reminded everyone of why this team is so much better with him in it. 

Gallagher provides the team with a focal point but also mobility and physicality. He is a rare hybrid forward who can do a bit of everything. Whether that be tracking back full-backs in a wider role or bruising centre-backs, the 28-year-old is a major asset for Eustace and Rovers.

The first goal was a clever bit of link-up. Similar to Tyrhys Dolan's third against Stoke City, it was Szmodics who was sent scampering away by a Gallagher flick, this time with his foot rather than his head.

Rovers have the option of playing up to Gallagher and knowing the ball will stick or be recycled. He has brought two goals for team-mates in the last week.

His goal was an ode to his running power. Gallagher can cover distance and without Ben Brereton Diaz, Rovers have really missed a direct runner. Szmodics and Dolan have a turn of pace but perhaps not the long-distance sprint speed that Gallagher can provide. He ate up the ground, shrugged off Liam Lindsay and poked past Freddie Woodman.

Let's not re-write history, there were some fair arguments for cashing in on Gallagher in January. Had Ipswich hit the £2million mark, we certainly wouldn't have argued it was bad business.

But the way he has come back into the team and what he offers, both and off the ball, makes him indispensable, especially for a team looking to play a more mixed style, rather than the possession-heavy approach of Tomasson.

The numbers back up the eye test too. Rovers are a far better team with Gallagher in it. Keeping him fit is the big challenge because of the physical load he puts in; he ran himself into the ground for 95 minutes at Deepdale.

It's a difficult balance because the drop-off to those deputising is sizeable. Or you play with someone like Dolan in that role, who is effective but offers different strengths.

Gallagher is someone that Eustace will look to build around, certainly until the end of the season. Perhaps off-the-field influences will dictate what happens from then.

With half an hour played, Rovers had carried out the perfect away display. Eustace's game plan had worked to perfection and the team were far more aggressive, on and off the ball. Each 50/50 was cheered like a goal by the away end who were lapping up the performance.

Rovers started the match with an average of 27.8, compared to the 23.6 that took to Ewood Park for the reverse fixture. Although they lost 32-year-old John Fleck early on, they will be frustrated to have surrendered their lead in four minutes of chaos.

In fairness, there was very little anyone could do about Robbie Brady's spectacular strike. It was a brilliant hit, arrowed into the corner with Aynsley Pears given absolutely no chance.

The second, though, was incredibly avoidable. Rovers didn't win first contact, it was hooked back towards the goal and it's eventually bundled in. Very scruffy and rather typical of Blackburn this season.

That was the exception rather than the rule, though. Rovers defended their box very well, particularly in open play. Dom Hyam, Kyle McFadzean and Scott Wharton were dominant in the air and Pears had very little to do besides tipping a late Alan Browne header around the post.

Rovers dominated the first 30 minutes but Ryan Lowe's side undoubtedly controlled the next half-hour. In previous away matches, Blackburn might have crumbled as the Deepdale crowd roared their side onto Rovers in the second half.

But they weathered that storm and the last third was more of a slog for both sides, on a very boggy, worn pitch. It was a blood-and-guts, fighting performance and Rovers did stand up to the task.

It wasn't perfect, how could it be when they were two-nil up, but it felt like a basis to build on. The first 30 minutes was a perfect blueprint of what Rovers van be at their best under Eustace. Their defensive frailties remain and that will be the biggest task for the new head coach in the coming months.

Four points from the week is not a terrible return for Rovers. There have been ups and downs, peaks and troughs, but supporters can expect that until the end of the season.