IT would be stretching it to say he is on fire, but at least Will Grigg’s Sunderland career is finally showing signs of smouldering to life.

At the fourth time of asking, Grigg claimed his first Black Cats goal following a £4m January move from Wigan Athletic, with his second-half penalty enabling his side to end their frustrating sequence of draws despite turning in another defensive display that was far from convincing.

Twice, Sunderland claimed the lead in the first half, and twice they were pegged back. Lee Cattermole and Tom Flanagan scored from Grant Leadbitter corners, but Tom Eaves equalised within 60 seconds of Sunderland’s opener and the Black Cats suffered a set-piece setback of their own as Brandon Hanlan stabbed home shortly before the break.

Grigg’s 66th-minute penalty restored Sunderland’s lead, and while Aiden McGeady might well have felt aggrieved that he was removed from spot-kick duty to enable his team-mate to break his duck, the Irish international was able to convert from 12 yards himself 11 minutes later as the hosts wrapped things up.

In an attacking sense, this was close to Sunderland at their free-flowing best, with McGeady’s class shining through and the Black Cats regularly committing a host of players into the box. Leadbitter’s delivery from corners has also added a valuable new string to the Wearsiders’ attacking bow.

Their defensive deficiencies remain alarming though, and a better side than Gillingham might well have caused them even more problems. On this evidence, the promotion run-in is set to be a real rollercoaster ride.

At least Sunderland were able to avoid what would have been an eighth draw in the space of ten games, and ensure they have taken five points from their run of three home matches in a week. In truth, that was probably the minimum requirement.

The game also enabled Jack Ross to pair Leadbitter and Lee Cattermole in the same Sunderland starting line-up, although it remains to be seen whether that becomes established as his first-choice selection.

The pair have mirrored each other for the majority of their careers – Cattermole growing up on Teesside before heading to the Stadium of Light; Leadbitter spending his formative years on Wearside before making more than 200 appearances for Middlesbrough – and remarkably, the game was the first time they had played alongside each other in a senior side.

The closest they had come previously was a 3-1 defeat to Chelsea in August 2009 that saw Leadbitter leave the bench to replace Cattermole, but while they might share a number of attributes in terms of their preferred playing style, Ross is adamant they can complement each other at the heart of the Sunderland midfield.

What he cannot have anticipated, however, is that they would team up to create Sunderland’s opening goal just five minutes in.

Leadbitter swung over a corner from the right-hand side, and while Flanagan failed to make contact as he tried to win a header at the front post, the ball deflected through to Cattermole, who was left with the simple task of stabbing home from six yards.

An early goal was just what Sunderland would have wanted to settle any pre-match nerves, but as has been the case on so many occasions this season, their defensive frailties meant they were unable to relax for too long.

Less than 60 seconds after Cattermole’s strike, Eaves, courted by Sunderland in the January transfer window, found himself galloping clear of a static Black Cats defence to secure possession in the 18-yard box.

He was forced to turn away from goal to evade goalkeeper Jon McLaughlin, but while Flanagan tried to get back to tackle the striker, Eaves was able to prod the ball into a gaping net.

It was a chaotic start, and the action showed no sign of relenting as Sunderland regained their lead just four minutes later.

Prior to Leadbitter’s arrival, the Black Cats had barely threatened from set-pieces all season. Since the 33-year-old signed, they have looked like scoring every time he has delivered the ball into the box, and after Jimmy Dunne and Jack Baldwin scored against Oxford United and Blackpool respectively, Flanagan followed Cattermole’s lead to make it four goals in four games from corners swung over by Leadbitter.

The delivery on this occasion was superb, with Leadbitter picking out an unmarked Flanagan at the back post, and the centre-half converting with a powerful downward header.

It was barely possible to draw breath, but the action was halted in an unfortunate manner as the recalled Chris Maguire sustained an ankle injury that forced his withdrawal in the 18th minute. Given how long the forward has had to wait to return to the side, he would have felt especially aggrieved as he hobbled from the pitch.

He was replaced by Lynden Gooch, and the American’s arrival did nothing to halt the open nature of the game. Sunderland were a threat whenever they committed bodies to the final third, but as had been the case against Accrington four days earlier, the hosts looked anything but resolute whenever Gillingham turned defence into attack.

Sure enough, five minutes before the break, the Black Cats shot themselves in the foot again. Just as Leadbitter’s corners had caused chaos at the opposite end, so Sunderland’s defenders proved completely incapable of dealing with a routine ball into their own six-yard box.

With too many home defenders failing to take responsibility, Leonardo Da Silva Lopes found himself in a shooting position close to the corner of the area. His effort was blocked, but the ball broke kindly for the unmarked Hanlan, who was able to sweep home.

Gooch shot straight at goalkeeper Tomas Holy on the stroke of half-time, but while Ross will have been pleased with the potency of Sunderland’s first-half attacking, he will surely have been alarmed at the lack of structure to so much of his side’s play. Playing off the cuff can easily stray into the realms of complete disorganisation, and Sunderland are currently treading a fine line between the two.

As if to underline the point, Lopes was afforded far too much room to drive in a shot that was unconvincingly parried by McLaughlin at the start of the second half, and found himself in a huge pocket of space again moments later as he fired over the crossbar.

Leadbitter forced Tomas Holy into a decent save down to his left as Sunderland continued to commit plenty of players forward themselves, and the game swung back in the home side’s direction shortly after the hour mark.

Reece James drilled over a low cross from the left, and Lopes tripped Luke O’Nien as the full-back was shaping to shoot. It initially looked as though McGeady would assume responsibilities from the spot, but Grigg pulled rank and successfully opened his Sunderland account as he side-footed home.

As it turned out, McGeady did not have to wait long for his own turn from the spot, with O’Nien winning a second penalty with 13 minutes left. Regan Charles-Cook swept away his opponent’s trailing leg, and this time it was McGeady who stepped up to claim his tenth goal of the season.