Finlay Pollock almost marked his full debut with a goal when the 17-year-old's first-half strike came off the post.
Neilson told Premier Sports: "I was delighted for him, a big Hearts fan from a big Hearts family. It was brilliant for him. He could have scored but at least he is getting there. I think he has a big future ahead of him."
Neilson also introduced midfielders Aidan Denholm and Connor Smith during the second half.
"In these cup competitions, it's important you win the game and get some game time for your senior players but you also have to try and use it for the young kids to give them some experience of playing here against senior players," Neilson said. "I was delighted with the two of them."
Neilson was also delighted with his team's overall performance after goals from Andy Halliday, Liam Boyce and Gary Mackay-Steven made it two wins from two in the tournament.
Neilson told Premier Sports: "We took a bit of time to get used to them playing that number 10 with (Fraser) Fyvie in the pockets but once we figured it out we got a bit more control. We scored some goals and probably should have scored quite a few more.
"We still have a bit of sharpness to come but you can see with the movement and the runs they are making that they are creating chances."