Former Chelsea defender has complained that Mauricio Pochettino is using players in the wrong positions.
Ben Chilwell has sometimes been used as a left-winger, while other players are also deployed in positions they are not best known for.
The experiment has been a limited success as best, with Chelsea continuing to struggle in mid-table, and the manager still looking for more reinforcements in the winter transfer window.
Speaking to Gambling Zone, Gallas questioned Pochettino’s approach to his squad selections.
He said: “It’s difficult to understand why the players are playing out of position - I don’t get why the manager is doing this.
“If you have a left-back in your squad and he’s available, you have to play him. The club buys players to play on the weekend and you have to put the best players in that position on the weekend on the pitch.
“If your left-back is so-so, you still have to put them in. You can’t put a right-back at left-back or a centre-back there, that’s why Pochettino’s tactics have been difficult to understand.”
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