London (AFP) – Chelsea goalkeeper Thibaut Courtois believes the key to their stunning turnaround in form lies in the defence that has conceded just two goals during the club’s 12-game winning streak.

The Premier League leaders face Stoke City next at Stamford Bridge on Saturday aiming to secure a 13th consecutive league win in a run that started in the wake of a humiliating 3-0 defeat at Arsenal.

But while forwards Diego Costa and Eden Hazard, together with inspirational midfielder N’Golo Kante, have attracted most praise in recent weeks, Courtois says the revamped back-line has laid the foundations for the upturn in form.

He believes the defence has been transformed by Conte’s decision to switch to three following the Arsenal loss.

“Letting in only two goals is amazing,” Courtois told Chelseafc.com.

“After that Arsenal game we had to build a new thing and we did it well, and there is a lot of hard work in training. It was not just that we did a new formation and it will work.

“As a goalkeeper it doesn’t change much but now we are more solid at the back than at the beginning of the season, it is harder for people to break us down, and when they do try to score a goal I try to save it.

“Some other teams tried to defeat us as well with that formation but if it is well-worked like we do it, it is hard to break down and every day in training we do it a lot.

“That is why we have this run at the moment and we just try to keep it going and we will see in few weeks and months where we are standing, and hopefully we will be there in the race for the championship.”

– ‘Things go really fast’ –

Hazard declared the current team could be better than the Chelsea side that won the title under Jose Mourinho two seasons ago.

But Courtois warned the six-point advantage could quickly disappear.

“In the Premier League things go really fast so we just have to keep the focus on ourselves and play game by game and then we will see,” said the 24-year-old Belgian international.

“Stoke at home will be hard and then we go to Tottenham, to Leicester, they are all tough games, and after we have Hull, Liverpool and Arsenal.

“So it is an important moment for us and then we will see where we stand in February.”

Bojan Krkic could feature for Stoke after being told he has a future at the club by manager Mark Hughes.

The 26-year-old former Barcelona and Ajax midfielder has only featured eight times in the Premier League this season, scoring three times.

But with Wilfried Bony, Mame Biram Diouf and Ramadan Sobhi all departing for the African Cup of Nations in January, Hughes has assured the Spanish striker he has a future at the club.

“Bojan’s people came in and we had a discussion because he hasn’t had many starts of late,” said Hughes.

“I want to give him more opportunities and he will get more opportunities from now until the end of the season.

“We’ve got three attacking players leaving in January so if he gets that opportunity he will probably stay in the team.”