Manchester United manager Sir Alex Ferguson says his new counterpart at Southampton, Mauricio Pochettino, is an unknown quantity to him.
The Argentine, who had been out of work since being sacked by Espanyol in November, was handed the reins at St Mary's Stadium following the dismissal of Nigel Adkins on January 18.
And, ahead of the Saints' trip to Old Trafford in the Premier League on Wednesday, Ferguson has hit out at the club's chairman, Nicola Cortese, over that decision, before admitting to being unfamiliar with Pochettino.
"I don't know a lot about him to be honest," the United manager told reporters.
"Nigel spoke to me the day before he was sacked. You cannot understand these things.
"Their form had picked up, two defeats in 12 games. I have to be careful what I say about their chairman but apparently he's a work of art."
Pochettino began his reign with a 0-0 draw with Everton at St Mary's Stadium on January 21.