However, it was all about the Gunners from the 15th minute onwards when Danny Welbeck scored Arsenal’s opening goal. The Englishman scored his second of the evening in the 22nd minute when he latched on to a brilliant ball from Oxlade-Chamberlain.
Thereafter, it was the former Southampton man Theo Walcott, who rose to prominence with his 5th hat trick for the Gunners with goals in the 35th, 69th minute and the 84th minute.
In this segment, we bring to you how the players fared in the game between the Saints and the Gunners.
Harry Lewis – 5
The young Southampton keeper endured a tough evening as he was constantly let down by his defence. He could have done little to prevent Arsenal from scoring their first 4 goals in the game.
Florin Gardos – 4
The centre-back looked extremely shaky throughout his return and was caught out of position on numerous occasions. With Arsenal in marauding form, he failed to lead his defence and showed no sync with his partner Stephens, to make things easier for the visitors.
Jack Stephens – 4
After impressing against Liverpool in their League Cup semi-finals, Jack Stephens had an evening to forget against Arsenal. He failed to track Welbeck’s runs for the opening as well as the second goal and could be deemed guilty of not clearing the ball when he had the opportunity, which resulted in Theo Walcott’s opening goal of the evening.
Cuco Martina - 5
The former Feyenoord and FC Twente right-back had a mixed game. While he did look threatening going forward, he looked susceptible in defence and offered the opposition time and space to operate on the left flank, which they exploited to great effect.
Sam McQueen – 5
Going up against the duo of Walcott and Bellerin, who are blessed with great pace and skill on the ball, was never going to be easy for Sam McQueen. The young full-back was thoroughly exposed throughout the game and will take this as one of the cruellest, yet most effective learning experiences.
Pierre-Emile Hojbjerg – 5
The Danish footballer started the game slowly and looked patchy in possession as well as without the ball. While he did grow into the game, there is very little he could have done to repress the marauding Gunners.
Jordy Clasie – 6
One of the better Southampton players on the evening, Clasie kept things tidy throughout the game. While he did lose his grip on the game on numerous occasions, he did well to gather himself and continue with the good work.
Harrison Reed – 6
Playing as the deep lying midfielder, the gifted Reed, like many other Southampton players endured a tough evening. He was afforded very little opportunity to showcase his overall quality in the first half as he was restricted to defensive duties. His creative output did improve in the 2nd half when he was allowed to push forward in a desperate attempt to eke out a positive result.
Lloyd Isgrove – 5
The Welsh winger was ineffective in the first half despite his efforts to turn the game around in his side’s favour. While he did find some joy in the 2nd half, it was short lived as he was substituted for Dusan Tadic.
Josh Sims – 7
Sims was arguably Southampton's best player on the evening. He kept the Arsenal defenders busy with his incessant running and looked dangerous when he got into advantageous positions on the pitch. He was tidy in possession as well as with his passing. The 19-year-old was a constant menace for the Arsenal defence and won 5 out of the 7 take-ons he attempted to keep his side’s attack ticking.
Shane Long – 6
The Irish striker looked threatening alongside Sims and created problems in the opposition half whenever he could in the early stages. However, with the game seemingly out of Southampton’s sights in the 2nd half, he was rendered ineffective due to lack of quality service from midfield and was replaced by Nathan Redmond.
Dusan Tadic – 6
Coming on as a 65th-minute substitute for Isgrove, Tadic injected energy into the faltering Southampton line-up for a short while. However, he could do little to reduce the huge deficit faced by his side.
Nathan Redmond – 6
Like Tadic, Redmond was also an electric presence after coming on for Shane Long in the 64th minute. However, the Arsenal defence did well to deal with his threat.
David Ospina – 7
The goalkeeper had very little to do for most parts of the evening with the game predominantly being played in the opposition half. However, he rose to the occasion when required and made a few good saves. The only troubling moment was in the first half when he left his line to deal with a Southampton attack and was lucky to not concede with the goal unguarded.
Rob Holding – 6
The young defender took a while to completely deal with Shane Long. However, once he settled down, Southampton found the going tough with him forging a strong partnership in the centre of defence with Mustafi.
Kieran Gibbs – 6
Gibbs was put under pressure during the opening exchanges of the game when he afforded Martina time and space on the ball on the right flank. However, as the game got on, he asserted his quality on the game and dealt with his threat appropriately.
Shkodran Mustafi – 7
The leader of the Arsenal defence put in an imperious performance as he dealt with the threat of Shane Long and Josh Sims without much fuss. Dominant in the air and relentless on the ground, the German is finally getting into the groove and is proving to the world that he is one of the best in the business and the game against Southampton was in indication of the same.
Hector Bellerin – 7
Bellerin’s credentials as one of the best attacking full-backs in the league gained further strength after his calm yet impressive showing against Southampton. The right-back formed a fine partnership alongside Walcott on the right flank and troubled the Southampton defence throughout the evening.
Alex Oxlade-Chamberlain – 8
The performance against Southampton was one of the best performances put in by the former Southampton man Oxlade-Chamberlain. He set up Arsenal’s and Welbeck’s 2nd goal with a great ball behind the Southampton defence and was also responsible for his side’s 4th goal when he found Alexis Sanchez in an advantageous situation.
Ainsley Maitland-Niles – 8
The 19-year-old impressed on a rare start for the Gunners and made some impressive runs to keep the Saints’ defence on their toes. Despite being just 19-years old, the Englishman showed the calmness of a battle-hardened footballer and if this game is any indication, Arsenal fans would be keen to see more of him in the future.
Jeff Reine-Adelaide – 7
Reine-Adelaide put in a good shift at the heart of the Arsenal midfield. He was tidy with the ball at his feet and kept things tidy for his side in the middle of the park by making requisite tackles to help his side assert their dominance. Overall, it was a very pleasing performance from the youngster.
Lucas Perez – 7
The Spanish striker put behind an injury-plagued and indifferent season to put in one of his best performances in an Arsenal shirt against the Saints. He created Welbeck’s first goal with a neat flick and was also involved in his side’s third goal.
Danny Welbeck – 9
The returning English striker made an instant impact when he latched on to a Lucas Perez flick to find the back of the net, albeit with a little help from the crossbar. Welbeck then took down a great ball from Oxlade-Chamberlain before sliding it through the legs of the approaching Southampton defender and then followed up by creating his side’s third goal with a threatening cross into the box from the left-hand side.
Theo Walcott – 9
The scorer of Arsenal’s first hat-trick in an FA Cup since Nicklas Bendtner’s triple against Lleyton Orient in 2011, Walcott proved to be a handful for the Southampton defence. Solely responsible for his first goal as he made an irresponsible Stephens pay for his complacency, Walcott was on hand to finish 2 more brilliant moves to bag the 5th hat-trick of his career, against his former club Southampton.
Alex Iwobi – 7
Iwobi replaced Reine-Adelaide in the 72nd minute and put in a good shift to help his side run out comfortable victors on the evening.
Alexis Sanchez - 8
The Chilean superstar came on in the 65th minute to replace the marauding Danny Welbeck but still had ample time to create Walcott’s 2nd and 3rd goal to heap further misery on the Saints.
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