Saturday's 1-0 defeat at home to Newcastle has left the Premier League champions ninth in the table, 15 points behind leaders Arsenal.
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|5/4||Manchester United are 5/4 with BetVictor to finish in the Premier League top four|
"In any transfer window you don't want to be bringing in a full batch of players, so I think there's a period of time that it takes," he told reporters.
"The last one was a difficult one after just joining the club, so we've got a window in January where, if we think if it's right for the club, we'll do so.
"If not, we'll look again in the summer. This club is always looking to bring in the best talent and that won't change.
"I don't think I'll feel under pressure personally to do it [buy in January] as I'll try to do the right things.
"I tend to take my time and try to assess what are the best talents to bring in. You can see that from the players I brought in at Everton."