Arsenal are nine games away from lifting the Premier League trophy for the first time since 2004, having moved eight points ahead of defending champions Manchester City.
There could yet be some twists and turns in the title race, however, with Arsenal set to visit the Etihad Stadium to face Man City later in the month.
Lacazette spent five years at Arsenal – scoring 71 goals in 206 games – but the Gunners never challenged for the title during his spell in north London.
Despite this, the Frenchman says Arsenal’s success this season has not come as a surprise as he heaped praise on his former manager Arteta.
‘Arsenal? I’m not surprised,’ Lacazette said. ‘I worked with the coach so I know how well he works.
‘I’m not surprised by the club’s success, and I’m happy for my former team-mates there.’
Manchester City, who have won four league titles in five years, marked their return from the international break by thumping Liverpool 4-1.
But Arsenal responded with a 4-1 win of their own against Leeds United, with Arteta subsequently hailing his team and Gabriel Jesus, who scored his first goals since a long injury lay-off.
‘After an international break you do not know if they are in the frame of mind to come back and do the things necessary to win this league,’ Arteta said. ‘I am really happy with the performance.
‘They made it tricky for us. We lost the ball in bad areas to a team that put four really fast players than run in transitions. After, we took control of the game and we’re really good in the boxes today.
‘I am so happy for him [Gabriel Jesus] after all the work from him and the staff throughout the last five months. Today, he got rewarded for that.’
Premier League leaders Arsenal travel to Anfield to face Liverpool on Sunday.
Lacazette’s powers appeared to be on the wane towards the end of his Arsenal spell but the 31-year-old has enjoyed a superb start to his career at Lyon, scoring 21 goals in 28 appearances.
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