The Irishman's first Dundee derbies were in July and August when United won 3-0 on each occasion and the Dark Blues took a while to get going following their late call-up to the top flight.
Now, though, Dundee have won three of their last five in all competitions to cut the deficit at the foot of the table and Dillon knows United will have to be at the best when they cross the street to play.
Dillon said: "I knew it wouldn't take them long to start picking up points - I didn't doubt that - and I'm not really surprised that they have picked up points lately.
"They've got some really good players, they've got a great backing from their fans, no matter where they go.
"They've got quality all over the pitch. It's just a case of hopefully getting things happening for them.
"Obviously we don't want that happening on Sunday. We'll be trying to make sure we can get three points for ourselves and forget about them."
Dens Park was full for the pre-season match in July which came days before Dundee took Rangers' place in the SPL.
It was strange for Dillon to experience such a boisterous atmosphere for a friendly and gave him an idea of what to expect this weekend.
"I had my first competitive derby earlier on in the season," he said.
"I played in the friendly beforehand at Dens - it was interesting.
"It was a slightly different type of atmosphere, our fans in the minority.
"We walk up together. The first time I did it was pre-season and it was a nice leisurely stroll because it was lovely and warm.
"I think we'll have a bit of a pace on getting up this time, with the weather being so bad.
"It's different. It's something you look forward to doing."
Dillon missed the Scottish Cup win at Stranraer with a thigh problem but is set to be included tomorrow.
"It's getting there. It's definitely improved," he said.
"I haven't been involved (in training) as much as I would like to be, but I'm quite optimistic, as I always am."