MANCHESTER, England -- Jose Mourinho said it is not certain he will be able to strengthen his squad in January while suggesting Manchester United's clout in the transfer market is not what it once was.
Mourinho takes his team to Southampton on Saturday sitting seventh in the Premier League table, 14 points off the top and seven adrift of the top four.
He will have the chance to add reinforcements in January to help make up the ground but the Portuguese coach is not expecting big changes.
"Honestly, I don't think we are going to sign," the United manager told a news conference on Friday.
"If we do, I would say one player. I don't see us going more than that."
Mourinho has been linked with a move for a defender after missing out in the summer, but warned supporters it may not happen -- in part because he believes United are not able to dominate the transfer market as they did in the past.
Where once they were able to take their pick of top talent, Mourinho suggested fans may have to temper their expectations to reflect the growing group of clubs who can match the financial might at Old Trafford.
The 55-year-old used the example of Tottenham to highlight his point, explaining that the days of plundering the north London side for their best players -- as Sir Alex Ferguson was able to do more than once -- are over.
"Is Manchester United, by its history, by its dimension, bigger than Tottenham?" he said.
"With all respect, Tottenham is an amazing club but I think everybody would say yes. Can you buy Tottenham's best players? No, because they don't sell.
"Of course, they are so powerful that they can say no. A few years ago, who was Tottenham's best player? Michael Carrick. And a few years later, who was the best player? [Dimitar] Berbatov.
"Can we go there now and bring Harry Kane? Dele Alli, [Christian] Eriksen, Son [Heung-min]? Can we go there and bring those players here? No. So who is more powerful now? Them or us?
"I know that we have to do better than what we are doing, absolutely, we have to do better, but one thing is to do better and another is to compare ourselves with what Manchester United was in the past because it is impossible.
"Not just because Manchester United was fantastic, but because there was a big difference to the others and now it is not like that."
Sources have told ESPN FC that United have money to spend in January but will only splash the cash if the right player becomes available.
Despite being valued at more than £2.8 billion, Mourinho insists the club cannot throw "crazy money" at potential signings and instead have to shop in what he calls "the second tier."
"Football has changed," he said.
"It's more difficult to buy players of a high, high, high level. The clubs are more powerful. The clubs don't want to sell, and to sell is to go to absolutely incredible levels. Before the smaller clubs were almost begging the big clubs: Get my best players. I need to sell. Please, you are powerful. Buy my best player. At this moment, they don't want to sell. They don't want to sell.
"It's more difficult to make the team better and stronger with buying.
"The transfer market is very difficult unless the clubs want to go to what I call crazy numbers. You have no chance in the market unless you go to crazy numbers, or instead you go to what you call the second-level players and still have crazy numbers, but that second level is the level people say, and I agree, that's not what Manchester United is."