Southampton legend Matt Le Tissier says that Tottenham Hotspur manager Mauricio Pochettino has a weakness in his ability to make substitutions.
Although Pochettino did a brilliant job at the Saints, where he guided the club the eighth place in his first full season, Le Tissier still saw an inability to change a game by using his bench.
"I always felt his substitutions were always very samey-samey, he never really changed his formation much to get back into a game," he said to the Express.
There were fears that Southampton's form would dip after Pochettino left, alongside a number of key players this summer, but the club have bounced back.
Under the stewardship of Ronald Koeman they appear even stronger than they did last season and are currently in second position.
It is in stark contrast to Spurs, who have struggled to pick up points under the Argentine.
The club are winless in the league in four games and Le Tissier has warned Pochettino that he may be about to find out that the grass isn't always greener on the other side.
"He had a group of players at Southampton who were willing to learn, not experienced Premier League players, and were happy to take on board the manager's principles," he said.
"He has gone to Spurs and it is a very different group of players. They are a squad of players he is having to evolve and it might take him a little bit longer to get the effect he is after.
"Will he get that, though? You would like to think that Tottenham might have learned their lesson over sacking managers too early but there have been quite a lot of managers who haven't been given time!"
Despite Le Tissier's criticism, there is still optimism about Pochettino's appointment at Spurs and much of the blame has been put on the club's players for their poor start.
Tottenham have lacked a cutting edge during their opening few games this season and they know they will have to find their shooting boots soon if they are to reach to the top four, as they had hoped before the campaign begun.
This weekend they take on Southampton and Pochettino will be determined not to allow his former club to get any further ahead of Spurs, even at this early stage of the season.