The Magpies' big spend has yet to be vindicated with results on the pitch.
“There’s been a lot of criticism of players coming in but this is the Premier League, and they have time to adjust. It takes time," said the former Derby boss.
The Magpies were among the highest net spenders in Europe this past transfer window, but results on the field suggest the new boys have failed to settle in.
Chancel Mbemba has been the most impressive of the four major signings, and his early form alongside Fabricio Coloccini looked promising.
The Argentine has proved to be the weak link in recent games, however, meaning the young Belgian is already emerging as first choice centre-back.
Georginio Wijnaldum started the season on fire with a great debut goal, but his influence has since waned.
The former PSV man is undoubtedly a quality addition, however, and he is likely to return to form sooner rather than later.
Florian Thauvin, on the other hand, has been a complete disappointment and has failed to bring the excitement and directness that was anticipated on his arrival.
The Frenchman has struggled to showcase his talents in the Premier League and has left fans wondering if he is indeed an upgrade on the departed Remy Cabella.
Serbian prospect Aleksandar Mitrovic has yet to stay on the pitch long enough to be assessed, but served the last instalment of his three-match ban on Wednesday night.
He is likely to return to the first XI for the Chelsea clash this weekend, and McClaren is confident he will soon start to prove his worth.
“He has showed enough spirit, fight and will to win. Probably overly!", said the Newcastle manager in the Chronicle.
“He’s demonstrated that and he’s showed that in training. We expect high things of him.”