Louis van Gaal has rejected suggestions that Manchester United must bolster their defence in the January transfer window.
Van Gaal claimed United have "more than enough" defensive cover and quality, despite Chris Smalling's groin problem further stretching resources after he was forced off in the first half of the 2-1 win against Southampton.
Robin van Persie's brace secured victory at St Mary's on Monday, but the Red Devils still struggled defensively.
And despite having to switch midfielder Michael Carrick into a makeshift defensive role midway through the game, Van Gaal was adamant that his squad does not need improving.
"When you have injuries you cannot solve the problem otherwise," Van Gaal said. "Do we have to buy players? No. We have more than enough."
Van Gaal's defence of his squad depth did little to mask United's problems at the back.
Van Persie converted United's only two chances on the South Coast as Van Gaal's men moved to third in the Premier League with a fifth straight win. Southampton pressed continually, though too often failed to deliver the killer blow.
Marouane Fellaini's disappointing performance forced Van Gaal to haul youngster Paddy McNair off before half-time in the hope Ander Herrera could add midfield bite.
That led to Carrick's switch to the back, with fit-again Jonny Evans replacing Smalling after his groin injury.
United are still missing Luke Shaw, Rafael, Phil Jones and Daley Blind, and that injured defensive quartet formed the foundation of Van Gaal's justification of his squad depth.
United host Liverpool at Old Trafford on Sunday, with former defender Gary Neville predicting the clash could descend into pub-league standard.
England coach Neville claimed United "got away with murder" at St Mary's, before tipping the Liverpool clash to resemble "The Dog and Duck vs. The Red Lion."
The unimpressed Van Gaal warned Neville to "pay attention to his words," asking reporters to interpret his comments however they saw fit.
Neville later denied talk of a rift with Van Gaal when asked about a "feud" on social media.
"@r1fgm: @GNev2 the press mentioning a feud between yourself and Van Gaal. What feud?" One that will be created that doesn't exist
- Gary Neville (@GNev2) December 8, 2014
Van Gaal said he hopes Van Persie is now approaching top form after a post-World Cup lull, but played down talk about his side's growing momentum.
"I hope that he is improving, I have to say I was very pleased with his performance and also his goals," he said of Van Persie. "The second goal was not so easy, because the ball from Wayne Rooney was coming for his right foot and he took it with his left; so it's a nice touch.
"Momentum, things of this sort, these are rhetorical questions. It's fantastic to be third in the table, but I had hoped we would manage that with a better performance."