“Insanity: doing the same thing over and over again and expecting different results.” Although whether Albert Einstein actually said these words remains unclear, never has a quote so eloquently summed up the plight of a Premier League football club.

In spite of their victory against Middlesbrough here at the Riverside Stadium, courtesy of goals from prized possessions Alexis Sanchez and Mesut Ozil, Arsenal remain a side caught on repeat.

Arsene Wenger made six changes from the side that was humiliated at Selhurst Park - the first time the Gunners had lined up with three at the back since May 1997 - but this was not enough to cover the cracks and hide his side's lack of coherence.

Middlesbrough vs Arsenal player ratings Show all 22 1 /22 Middlesbrough vs Arsenal player ratings Middlesbrough vs Arsenal player ratings Brad Guzan – 6 out of 10 Dealt with most that Arsenal threw at him but should have done much better with Sanchez’s free-kick. Getty Middlesbrough vs Arsenal player ratings Antonio Barragán - 6 Solid if unspectacular night on the right side of defence. Getty Middlesbrough vs Arsenal player ratings Ben Gibson – 7 Marshalled Giroud well and handled the Frenchman’s physicality without too much trouble. Getty Middlesbrough vs Arsenal player ratings Daniel Ayala -7 Capable in defence but should’ve done better with second-half header. Getty Middlesbrough vs Arsenal player ratings George Friend - 6 Exposed by Oxlade-Chamberlain at times but solid enough in relief of the injured Fabio. Getty Middlesbrough vs Arsenal player ratings Adam Clayton – 5 Typically workmanlike in defence but a poor challenge cost Boro dearly from the resulting Sanchez free-kick. Getty Middlesbrough vs Arsenal player ratings Marten de Roon – 6 Failed to really assert himself on the game. Getty Middlesbrough vs Arsenal player ratings Grant Leadbitter – 6 Ugly first-half tackle on Ozil could’ve earned him more than just a yellow but showed well in attack. Getty Middlesbrough vs Arsenal player ratings Stewart Downing - 7 Rolled back the years with an inch-perfect ball for Negredo’s goal. Getty Middlesbrough vs Arsenal player ratings Alvaro Negredo – 7 Quiet night as the home side’s focal point but took his goal with a poacher’s instinct. Getty Middlesbrough vs Arsenal player ratings Gaston Ramírez – 7 Boro’s brightest attacking threat and looked the home side’s most likely to break the Gunners back line down. Getty Middlesbrough vs Arsenal player ratings Petr Cech - 6 Not tested a great deal and deserved better from his defence for Negredo’s goal. Getty Middlesbrough vs Arsenal player ratings Gabriel – 6 Always on the edge of an utter calamity the Brazilian managed to avoid any tonight and looked better in a three. Getty Middlesbrough vs Arsenal player ratings Laurent Koscielny – 7 Arsenal’s best defender but will have wanted to do better with Negredo’s goal. Getty Middlesbrough vs Arsenal player ratings Rob Holding – 7 Definitely a player for the future if not right now. Getty Middlesbrough vs Arsenal player ratings Alex Oxlade-Chamberlain – 7 Pushed on well down the right flank and offered positional discipline going the other way too. Getty Middlesbrough vs Arsenal player ratings Aaron Ramsey – 7 Neat and tidy as ever and added a dash of quality with a deliciously composed chested knock down for Ozil’s goal. Getty Middlesbrough vs Arsenal player ratings Granit Xhaka – 7 Doesn’t know whether he’s coming or going but plenty of energy if not so much discipline from the Swiss. Getty Middlesbrough vs Arsenal player ratings Nacho Monreal – 7 Added some good balance on the left and thrived with the added attacking responsibility. Still a little clumsy in the defence. Getty Middlesbrough vs Arsenal player ratings Mesut Özil – 7 Took his goal with the composure required and added the class when the Gunners needed it most. Getty Middlesbrough vs Arsenal player ratings Alexis Sánchez – 8 Not one of the Chilean’s best games yet was still the outstanding performer scoring one and creating another. Getty Middlesbrough vs Arsenal player ratings Olivier Giroud – 7 Didn’t threaten as much as he would’ve liked but added the focal point that Arsenal lack with Sanchez up top. Getty

Middlesbrough, in contrast, will feel hard done by. The home side put in a valiant performance, with Alvaro Negredo snatching a deserved equaliser minutes after the restart, and enjoyed the lion’s share of chances to push Arsenal to the edge.

Wenger had conceded earlier in the week that he was unsure if questions over his own future at the club were affecting his players’ form - "I honestly don't know…I hope not” - but tonight was yet another stark reminder of just how much Arsenal have struggled this season, especially on the road.

As such, it was Middlesbrough who started brightest, with the likes of Gaston Ramirez and Grant Leadbitter asking testing questions of the Arsenal backline. While the visitors looked nervy and scatty - with Alex Oxlade-Chamberlain drawing the first card of the game after just two minutes - the home side looked confident and enthused by the challenge ahead. Come the 15-minute mark Steve Agnew’s men had recorded three attempted shots to Arsenal’s zero, with captain Leadbitter’s fizzing shot coming closest.

Indeed, Boro’s persistence almost paid off after the ball was buried into back of the net in the 22nd minute - only for the flag to go up. Arsenal had failed to clear a free-kick beyond the edge of their box, allowing Gaston Ramirez to pounce on the loose ball and pick out Marten de Roon ahead of him. From five yards out, the unmarked midfielder did the rest but his offside position denied the home side what would have been a deserved opener.

Arsenal’s chances, in contrast, were few and far between. A wild, acrobatic half-volley from Aaron Ramsey could only force a corner ball on the half-hour mark while a promising cut-back from Oxlade-Chamberlain, delivered on the right-hand side byline, was intercepted by Leadbitter to deny Olivier Giroud a close-range shot on goal.

Middlesbrough hit back - and hard. A sustained period of pressure culminated in a series of testing deliveries from the right flank that pushed the visitors to the limits of their defending capabilities. With his height and presence in the box, the returning Laurent Koscileny was repeatedly called upon to deter the home side. Were it not for Boro’s indecision and lack of clinical edge, Steve Agnew’s men could have headed into half-time on top.

Alexis Sanchez strikes for Arsenal (Getty)

But as been the case for much of Arsenal’s season, the side’s redeemer stepped up to deliver. Dead centre of the goal, and just three yards out from the Middlesbrough box, Sanchez struck with a delicious curled free-kick to pick out the top left corner. A sombre-looking Wenger rose to celebrate his side’s 3000th away goal in English league football and a breakthrough at last.

Their lead lasted a matter of minutes, though. Boro emerged from the break defiant and soon had their equaliser. A misplaced Sanchez pass released Stewart Downing who broke with surprising speed down the right. A neat cut-back ensued, followed by a pin-point precise delivery. Holding off pressure from Koscielny, Negredo stuck out an optimistic leg near the front post to guide the ball past Petr Cech and into the back of the net.

Sanchez celebrates his goal (Getty)

Buoyed by their goal, Boro pushed on. Downing had the chance to become creator-turned-goalscorer moments later but sent his effort from 10 yards out into the stand behind. Daniel Ayala followed this up with his own missed attempt. Leaping courageously through the box to meet Leadbitter’s nod-back, the defender almost added Boro’s second but his effort was blocked and the danger eventually cleared.

Still Middlesbrough came. Substitute Adama Traore marked his arrival with a promising surge into the Arsenal box but was blocked by Koscielny. Calls for a penalty filled the Riverside Stadium but referee Anthony Taylor waved on play.

Mesut Ozil strikes from close range (Getty)

But, once again, Arsenal pulled ahead against the run of play. Sanchez’s floated cross into the box was met by Ramsey’s chested knock-down, setting up Ozil for a low-driven strike that found the bottom left-corner. The German had delivered another underwhelming, lifeless performance but, on this occasion, paid his dues with a well-taken goal.

Boro refused to roll over, fighting to the bitter end, but their determination failed to deliver the desired result. A cruel conclusion for a side that deserved more.