SERENDIPITY is defined as ‘the development of events by chance in a happy or beneficial way’. In relation to Sunderland’s summer pursuit of Papy Djilobodji, it came in the somewhat unusual form of a lost passport.

Having spent the second half of last season on loan at Werder Bremen, with his late winner on the final day of the campaign ensuring the German club did not suffer relegation from the Bundesliga, Djilobodji entered this summer hoping to force his way into the first-team picture at Chelsea.

His prospects were enhanced by a successful pre-season tour of Austria, which saw him make two appearances under new Chelsea boss Antonio Conte, and had he continued on to the United States and impressed there too, he might well still be employed at Stamford Bridge.

As it was, a missing passport meant no American visa, no American visa meant no further opportunities to convince Conte, and by the time Chelsea’s Italian manager returned to English shores, he had concluded he could do without the 27-year-old centre-half.

Sunderland came calling, and while Djilobodji had been unable to cross the Atlantic, he was persuaded to make the somewhat shorter trip to Wearside to become David Moyes’ first signing at the Stadium of Light.

“I left on loan to go to Germany last season and thought I had quite a good time there,” said Djilobodji, who has emerged as Moyes’ first-choice defensive partner for Lamine Kone following the sudden August departure of Younes Kaboul. “I came back to Chelsea in the summer, and did a pre-season in Austria. I played in two friendly games, and thought I played well.

“But then I lost my passport, and there were a few problems that meant I wasn’t able to go to the United States for the games over there. Then, when the team came back, they told me that Sunderland wanted to talk to me. When that happens, it normally means they want you to go.

“I had a chat with Sunderland, and it seemed to go really well. I was happy to move, and I’m still really pleased I made that decision. It’s true to say that it’s not the same, and the clubs are in different positions at the moment.

“But you take risks in football, and if you take your chance and have a bit of luck, who’s to say you might not end up in a better position in the long run? Maybe losing my passport was fate. Maybe it was just the way things were meant to be.”

Chelsea’s loss was Sunderland’s gain, although there are Black Cats supporters who might contest that assessment after a number of erratic displays that saw the Senegalese defender struggle to come to terms with life in the English top-flight.

Djilobodji’s critics have perhaps been swayed by the fact his transfer fee was announced as £8m when Sunderland’s initial payment is understood to have been significantly lower, although it is hard to deny that some of his early-season displays set alarm bells ringing.

He was much better in the victory at Bournemouth that preceded the current international break, and while he has played in both France and Germany as well as spending a season kicking his heels in Chelsea’s reserves, he concedes he was somewhat unprepared for the physical and mental onslaught of an extended run in the Premier League.

“It’s a lot more testing than I had expected or known, especially from having played in France or Germany,” he said. “It’s the first time I’ve spent any time playing in England, and I do feel that the game is different here.

“As a defender, you need a lot more fighting qualities and a lot more concentration. But you also need discipline in the way you defend. I’ll try to work on all these things to be able to succeed in the Premier League.”

A steely determination has been a key part of Djilobodji’s character since he left his native Senegal in 2009 in order to join French amateur club Senart-Moissy. For a while, he lived on the floor of a friend’s flat as he battled to gain recognition, and his perseverance was eventually rewarded when he was offered a move to Ligue 2 side Nantes.

Senart-Moissy play in front of crowds of fewer than 1,000 in the French amateur set-up, but even that was a step up for Djilobodji, who had spent the previous two seasons playing with ASC Saloum in the Senegalese league.

The best African players tend to be cherry-picked by European clubs in their mid-teens, but Djilobodji remained in his homeland until he had turned 18, something he feels has toughened him up and enhanced his chances of succeeding in England.

“I played club football in Senegal for a couple of years, and I think that period was important for me,” he said. “Some players leave for Europe at a much younger age, but maybe this was just my way and the way I needed things to be to make sure when I did eventually make the move, I was ready.

“I spent longer playing in Senegal, and I think that made me tougher and more determined. The football there is a bit like Ligue 1 in France – maybe not quite at that standard – but spending time there taught me a lot.”

Last season presented another significant challenge, but having helped guide Werder Bremen to safety when all had looked lost, Djilobodji sees no reason why he cannot enjoy similar success with Sunderland this season despite the Black Cats’ current position at the foot of the Premier League.

“This is the second season in a row I’ve been involved in a situation like this, but life is never easy and I’m someone who tends to do better when I have a challenge,” he said. “Last season, it was a team effort that got us (Werder Bremen) to safety, and this season, it’s a real team effort that we’re putting in.

“It was important to get the result at Bournemouth, but we have to stay focused and give it our best shot in every game we play. As long as we work hard and give it our best shot in everything we do, we will be okay. In the end, hard work pays off.”