The 21-year-old has found the net nine times in the Premier League this season, six of which have come since caretaker manager Ole Gunnar Solskjaer replaced Jose Mourinho in December.
Rashford has already made more than 150 appearances for United despite his tender age and former England striker Lineker described criticism of his finishing as “nonsense”.
“The great, young players are always the key,” he told TalkSport.
“Marcus is a fabulous young talent. I love the way he plays.
“I have never understood this whole nonsense that he doesn’t look calm in front of goal.
“I always felt he was the polar opposite of that. People see him missing a couple of chances and then suddenly he’s not a natural finisher.
“I don’t know where they got that from, because I love the way he finishes.”
He continued: “He’ll obviously learn and get better along the way, but he’s got some superb characteristics to his game.
“He’s got great speed, great confidence, a great touch and he’s very humble.
“When he was an 18-year-old he was picking up the ball and taking corners and free-kick without hesitation.
“To me that shows a player who is hugely confident in his own ability, not one who chokes in front of goal.”
