"It was a hard-fought win against a decent United team. They've got good attacking options, and it's not often Dundee United fail to score," McInnes told Sky Sports News.
"The teams had a bit of respect for each other - both sides have a threat, but I think for the most part that was cancelled out. If the game was screaming out for a bit of quality, that was provided in the build-up to the goal.
"Calvin thrives on service, and he got good service for the goal. He was where he should be at the right time, and made the difference in getting the three points."
Aberdeen find themselves fourth in the Scottish Premiership after 10 games.