The arrival of the 23-year-old helps Southampton cover a defensive hole left by Romanian Florin Gardos, who faces seven months out due to a knee injury, while also reducing QPR’s wage bill as they adjust to life in the Championship.
“It’s a good opportunity for the player,” said Saints manager Ronald Koeman. “We need more competition in the centre-back position.”
Koeman said Caulker could ultimately have a longer term future at Southampton, who are paying QPR more than one million pounds for the player’s services according to media reports.
“It depends on what the player brings,” he said.
Caulker, who has made one appearance for England and played for Tottenham Hotspur, Swansea City and Cardiff City in the Premier League, said it was a chance to prove himself under a great manager.
Gardos made only 11 league appearances for Southampton last season but was expected to play a bigger role following the departure of Toby Alderweireld — who was on loan from Atletico Madrid — to Tottenham Hotspur.
Caulker, who has age and height on his side, will now be in the frame to compete with Maya Yoshida to partner captain Jose Fonte in the defence.
Koeman also told reporters he was looking for more players to build up a squad that plays Vitesse Arnhem, a club he once coached, in the third qualifying round of the Europa League on Thursday.
“I think we need some more players,” he said. “We have real competition in our squad. We are working on it. But sometimes you need more time. We are not in a hurry.”
(Reporting by Timothy Collings/Alan Baldwin; editing by Toby Davis)