The 17-year-old plays the majority of his hockey for Blackburn Hawks in NIHL North One, having come through the Bradford Bulldogs junior system.
No 2 goalie Finney left the Chiefs’ last month to become first-choice for Sutton Sting in the division below, leaving Walker to act as back-up to Gospel when not required by the Hawks.
But Gospel is ruled out for Sunday’s clash with the Bison through an upper-body injury that saw him struggle valiantly through Saturday’s 5-1 defeat against Bracknell Bees.
The Chiefs were unable to field a back-up netminder against the Bees, but Widnes Wild Under-18 goalie Jake Lowndes will fill that role against Basingstoke, with Walker getting the start.
“It’s a great opportunity for Harrison,” said Zajac. “He’s a very talented young kid and it’s his first taste of this level, so it will be a good chance to test himself.”
On Gospel’s injury, Zajac added: “He’s been absolutely great all year, but he’s played a lot of hockey.
“He’s been training with Nottingham throughout the week and also training with us as well as playing every game for us. He’s faced a lot of shots at times, especially when we were short on bodies, and it has caught up with him now.
“He’s definitely out for Sunday and I wouldn’t be surprised if it is going to be for a bit longer.”