The two sides got their Premier League campaign underway at St James' Park and it proved a physical game with plenty of challenges flying in.
Shortly after the restart, Alli found himself on the receiving end of a stamp from Jonjo Shelvey - for which the Magpies man saw red - before scoring the opener on the hour mark.
Alli told Sky Sports News: "We knew it was going to be a physical game. It's not an easy place to come. It happens sometimes. I'm sure [Shelvey] will be disappointed, it was important we stayed professional. I don't want to talk about it too much.
"I've had a few talks with the gaffer in the past [about my temperament]. I've been pulled up for my temper before but today we had to keep our cool. There was no need to react today."
Shelvey is the first Newcastle player to be sent off on the opening day of a Premier League season at St James' Park since Alan Shearer in 1999.