Wijnaldum plundered four goals, while Sissoko provided three assists as the Magpies won their first Premier League game of the season at the ninth attempt.
"The front four were excellent, especially Gini Wijnaldum," McLaren told Sky Sports.
"Individuals stepped up and that was the key thing.
"Moussa Sissoko showed strength and power and he showed why he is coveted by the top four. I thought the score could have been anything.
"We rode our luck and defended quite well. On the break we were terrific. I am relieved and the crowd got behind us from the first whistle.
"I am pleased for the players because it is been tough and hard. We had a tough week after [losing 6-1 to] Man City. We showed our strengths of what we are good at but we showed weaknesses by conceding two."
Wijnaldum - a £14.5million summer signing - became the club's first player to score four goals since Alan Shearer put five past Sheffield Wednesday in an 8-0 thrashing in September 1999.