It was a hapless start to the season. Newcastle's static right-back allowed Pablo Zabaleta's hopeful pass to somehow find its way through to Samir Nasri. The Frenchman duly slotted the ball past Tim Krul to complete a 4-0 win for Manchester City and the knives were out for Mathieu Debuchy. When you're being unfavourably compared to Danny Simpson, it's clear things are not going well.
Debuchy's sluggish efforts on the opening weekend came after a difficult first season following his delayed January switch from Lille. After making his debut in a goalless draw with Norwich, Debuchy was not part of another clean sheet for over seven months with a red card in the 6-0 home defeat to Liverpool in April an obvious low point.
Worryingly, the 28-year-old France international was showing signs of being unable to adapt to the English game. "The matches are two times as fast," admitted the player himself in an interview with RMC Sport. "There's more intensity. There are no stoppages. Every week we have difficult matches, even against the bottom team. Training is more intense. It's really different."
Playing the game at such pace tests fitness and technique but also demands high levels of concentration. Errors were a problem. "We experienced a difficult period," he added. "It's the first time that I was fighting against relegation. Every so often, I was a little more on edge. It's definitely down to that. I've got to cut out these mistakes -- I'm going to find a solution to them."
It seemed as though that solution had been found. And the turnaround in fortunes - for both player and club - was certainly spectacular. A sequence of seven Premier League wins from nine games lifted Newcastle into the top half of the table and included impressive victories over Chelsea, Tottenham and Manchester United.
All three of those wins were built on solid defensive performances as Alan Pardew's side managed to achieve three unlikely clean sheets. The last team to score more than once at St James' Park was Liverpool in October when the Magpies were reduced to 10 men in the first half and still succeeded in snatching a point. The role of Debuchy has been pivotal.
The modern full-back has become a marauding figure in the game, more inclined to provide an attacking outlet than offer cover for his centre-backs. But the combative Debuchy has been a key defensive figure at right-back, boasting some eye-catching statistics. Only the burly Branislav Ivanovic has won more aerial duels from full-back.
"He puts his life on the line every time in every game he plays," Pardew recently told the Newcastle Chronicle. That's reflected in his tackling with his tally of 64 being the highest by any Premier League defender so far this season. He's consistent too, making at least five tackles in seven different matches this campaign. No defender in the top flight can beat that record.
My style is to go into tackles.Mathieu Debuchy
"My style is to go into tackles," says Debuchy, a method that might explain his nine yellow cards for club and country this season. But if this paints a picture of an irresponsible character covering for positional mistakes, the image might be an inaccurate one. Interceptions are a valued defensive trait in the world of analytics and here too Debuchy ranks among the top Premier League full-backs.
This defensive contribution has been vital in giving Newcastle a platform from which to get results, but it has complemented rather than prevented his attacking instincts. "I'm allowed to push forward when appropriate and to participate in our attacks," explains Debuchy. "Last year it was a bit difficult because the manager wanted me to stay in position defensively."
Indeed, with 36 per cent of Newcastle's attacks coming from that third of the pitch - more than the other two zones - the right-hand side has been an important weapon for the team. In particular, the relationship with Moussa Sissoko has blossomed. The powerful midfielder is inclined to drift infield, opening up space for Debuchy to advance and it is reaping dividends.
"We have to enjoy them when they are playing together like this," midfielder Yohan Cabaye told Newcastle United's official website after the 3-0 win at Crystal Palace. "We have done very well down that side. The way they were together, their passing and crossing, was brilliant. A lot of our attacks came from that side and that helped us win the game."
Even in the recent home defeat to Arsenal, Debuchy was impressive in dealing with the threat of Santi Cazorla, clearing a Theo Walcott effort off the line and getting forward well. But last time out against West Brom, that old reckless side to his game emerged again as he was red carded for a wild lunge on Claudio Yacob. Newcastle went on to lose the game. Debuchy was culpable.
Newcastle will now be without their star full-back for two Premier League games, beginning with Sunday's televised clash with Manchester City. In some ways, last week's sending off at the Hawthorns represents a setback. But as the Newcastle fans peruse the team sheet and wonder how they will cope without him, there are also signs of just how far Mathieu Debuchy has come.