The former midfielder believes the Gunners man is learning how to play the striker role after being employed there by Arsene Wenger.
The star of the show at the King Power Stadium was Alexis Sanchez on the afternoon, as he scored a hat-trick to help his side secure a much-needed victory after back-to-back defeats.
But Walcott started the game upfront for the Gunners and played his part as he scored their equaliser when they had fallen behind to Jamie Vardy’s opening goal - and Murphy praised him for his display.
"He deserved a special mention," he told Match of the Day.
"[Against Leicester] he was playing on the shoulder all the time and that gives Arsenal a brilliant option. Every aspect of his game in the striking role was good. He was a constant threat all afternoon."
Walcott is learning how to play the striker role
The former midfielder also believes Walcott is learning with every game how to play the lone striker role.
Much was made of Arsenal’s failure to sign a high-profile centre-forward this summer, with many believing that not doing so was a big mistake as it would have pushed them closer to a potential Premier League title challenge.
Wenger, though, has backed Olivier Giroud and Walcott to score the goals necessary for this side this season and Murphy believes that the latter is slowly learning the striker role, having spent so long playing out on the wings for Arsenal.
"Theo’s playing that striker role and I think he’s picking it up," he added.
"He’s learning when to come to feet and when to go behind. He’s full of confidence and full of energy and you can tell he wants to play."