Southampton manager Ronald Koeman admits the introduction of Andy Carroll changed the game in his side’s 2-1 defeat at West Ham.
Koeman’s outfit went into the game in high spirits, having thumped Arsenal 4-0 on Boxing Day, and led 1-0 at the break and were looking comfortable at Upton Park.
However, Slaven Bilic brought on England striker Carroll during the interval, which prompted a West Ham revival – completed when the 26-year-old headed the winner.
“It’s not too difficult to explain. We spoke at half-time about our first half and what we could expect in the second half,” Koeman said.
“It was a different opponent with Carroll on the pitch – more aggressive, more direct football, and that’s more difficult. You need to control the game and in the first 20 minutes of the second half we lost more balls and made more mistakes, and out of two situations that’s the reason we lost.
“If you play so well in the first half and don’t score two or three goals and kill the game, then you can expect this.”
The defeat leaves Southampton 12th in the Premier League, seven points above the relegation zone and seven points off a Europa League spot.