Arsenal manager Mikel Arteta hailed Mauricio Pochettino as a 'big brother' and believes he is already turning things around at Chelsea.
The pair played together for a year at Paris St Germain, both arriving in 2001 and striking up a friendship that lasts until the present day.
They have since gone on to become top coaches - but their meeting at Stamford Bridge on Saturday will be the first time they have faced off as opposing managers.
Pochettino, 51, is 10 years older than Arteta and while they may have signed for PSG at the same time, the Arsenal boss credits the Argentine for taking him under his wing.