Coaching staff intend to nurture the 18-year-old carefully after handing him a senior debut in the final minutes of Saturday’s draw at Ross County.
Kirk, the son of former Hearts striker Andy, has scored regularly for the club’s under-18 side this season and was rewarded with a first-team outing in Dingwall after Liam Boyce suffered cramp.
“It was good for Mackenzie to come on,” Neilson told the Evening News. “He’s had a wee injury, then he came back in and scored in the Youth Cup semi-final recently. He has been doing well and he is a natural finisher.
“There was only a couple of minutes to go on Saturday and Boycie had cramp. We were going to take him off so it was time to give the boy a chance. We put him on and, if there’s anybody at the club going to nick a goal, it’s Kirky. He’s that type of player.”
Neilson stressed that young Kirk shouldn’t be compared with his father, who scored 35 goals in 134 appearances for Hearts between 1999 and 2004.
“He’s different and he is still growing into himself. I think he’s got a chance,” continued the manager. “He isn’t ready to be a regular in the first team. Mackenzie was on the bench at the weekend because we had a number of injuries. He still has a distance to go on his pathway.
“He’s got to play consistently in the under-18s, which he has been doing. He is probably going to need a loan deal [for experience], and then get himself back into the group again. Saturday was great for him. He got on the pitch and he got a touch so he will be on a high. I’m pleased for him.”
Riccarton medical staff are still treating injuries ahead of Saturday’s Edinburgh derby against Hibs at Tynecastle. Boyce and Toby Sibbick both suffered cramp against Ross County but are expected to be available for the first of two successive Capital clashes.
Winger Gary Mackay-Steven is starting full-contact training following surgery on a broken hand. Provided there is no adverse reaction, he is likely to be back in the Hearts squad for this weekend.
“Boycie had cramp in his calves so there was no point taking any risk on Saturday when it was 1-1 with a couple of minutes to go,” said Neilson. “It was best to just get him off and that’s why we put Mackenzie on.
“Sibbick had cramp as well. He hasn’t played a lot of games recently, which is one of the issues when we don’t have a reserve league. Gary Mackay-Steven should be back this weekend. He had an operation on his hand and it’s taken time to heal but he has been doing all the running.”
Midfielder Cammy Devlin remains a doubt for this week, while defenders John Souttar and Michael Smith are still recovering from ankle and back issues respectively. Beni Baningime is out until nearer the end of the year with a cruciate ligament injury.