IF pre-season is all about learning lessons, then Tony Mowbray’s main takeaway from Sunderland’s final summer friendly against Hartlepool United will be that his B team is exactly that.

A cobbled-together side comprised largely of youngsters, fringe players and a couple of first-team hopefuls lost to a Hartlepool United team readying themselves for life in the National League following last season’s relegation. Not exactly the ideal way to prepare for Sunday’s Championship opener against Ipswich Town.

In truth, none of Sunderland’s pre-season results will matter if they claim all three points at the Stadium of Light this weekend, but while tonight’s defeat can easily be written off as an irrelevance given the experimental nature of Mowbray’s line-up, it nevertheless exposed some of the limitations that clearly still exist within the squad.

The season might be starting at the weekend, but the transfer window does not close until the end of the month and that is a date that could still have major ramifications in terms of how Sunderland’s season pans out. The need for at least one new striker remains obvious, with the Black Cats chronically short of options in the final third.

In terms of Sunday’s opener against Ipswich, it was surely instructive that Mowbray opted to start tonight’s game without all 11 of the players that started last weekend’s home friendly with Real Mallorca.

Does that mean last weekend’s side will be the team that kicks off when the real business begins? There has to be a good chance. Danny Batth could perhaps dislodge Luke O’Nien at centre-half, and Alex Pritchard would be an alternative option to Hemir in attack, but the vast majority of tonight’s starting line-up will have to content themselves with a place on the substitutes’ bench at the weekend. Given the way they played, that is probably no more than they deserve.

It can be dangerous to read too much into pre-season matches, but Sunderland’s ragged display against National League opposition hardly augurs well if Mowbray is forced to delve into the depths of his squad in the next few weeks.

Admittedly, if you’re going to get an experiment wrong, it’s better to do it in a pre-season game rather than a match that really matters, so while the sight of Niall Huggins being moved out of his makeshift central-midfield role after just 25 minutes was no doubt chastening for the youngster, it at least taught Mowbray something about the defender’s current limitations.

Having started with a five-man defence, Mowbray switched to a flat back four midway through the first half, by which time his makeshift side was looking thoroughly bedraggled.

Pools scored three goals in that first quarter of the game, and might well have added more had Lynden Gooch not been moved infield to add some of the much-needed bite that was missing when Huggins was playing alongside teenager Chris Rigg in the early stages.

The home side’s opening goal came just three minutes in, and was the direct result of a Sunderland error. Batth rolled the ball to Huggins, who slipped and conceded possession in his own area. Callum Cooke teed up Chris Wreh, who curled home from the edge of the box.

Sunderland levelled in the 12th minute, courtesy of a piece of technical brilliance from Pritchard. Gooch was wrestled to the floor just outside the box, and Pritchard stepped up to curl a superb set-piece into the top corner.

Parity didn’t last for long though, with the Black Cats’ defence collapsing as Pools midfielder Anthony Mancini claimed two goals in the space of two minutes midway through the first half.

His first was the result of a composed first-time finish from close to the penalty spot after Wreh helped David Ferguson’s low cross into his path, with Sunderland’s defence having switched off completely to leave Mancini unmarked.

The second came after Sunderland conceded possession cheaply from the subsequent kick-off, and saw Manicni advance unchecked towards the edge of the area before firing a crisp low finish past Matty Young.

Mowbray kept his half-time tinkering to a minimum, with Anthony Patterson replacing Young in goal in the only alteration for the start of the second half, and with Pools boss John Askey making a host of changes at the break, Sunderland were initially more threatening after the break.

Abdoullah Ba dragged a shot wide after a neat one-two with Jewison Bennette, although Bennette did not really look ideally suited to the central-attacking role he was asked to fill after the break. The Costa Rica international undoubtedly has his strengths, but leading the line against a physical non-league defence is not really one of them.

His night improved almost immediately when he was moved out to the right, with Michael Spellman coming off the bench to lead the line, with his 65th-minute goal reducing Sunderland’s arrears. Traintis’ long ball sent Bennette scampering down the right, and after cutting into the area, he bent a clinical finish into the far corner.

Any hopes of a comeback quickly disappeared though, with Pools adding two late goals. Mani Dieseruvwe rolled home from the penalty spot after Jake Hastie had been fouled by Gooch before Joe Grey found the net from an acute angle after Rigg gave the ball away cheaply in his own half.

HARTLEPOOL (5-3-2): Jameson; Seaman (Lacey 46), Dodds (Darcy 46), Onariase (Cook 46), Pruti (Dolan 46), Ferguson (Stephenson 63); Crawford (Robinson 63), Cooke (Burton 46), Mancini (Hastie 46); Umerah (Dieseruvwe 46), Wreh (Grey 46).

Sub (not used): Dixon (gk).

SUNDERLAND (5-3-2): Young (Patterson 46); Gooch, Traintis, Batth, Johnson (Burke 72), Taylor (Spellman 63); Rigg, Huggins, Ba; Bennette, Pritchard.

Subs (not used): Hume, Cirkin, Ballard, Bellingham, Clarke, Roberts, Hemir, Neil, Ekwah, Gardner, Middlemas, Bainbridge.