Shearer questioned how many times Rashford has started up-front since Lukaku moved to Old Trafford.
Despite Rashford’s youth, Shearer is convinced Mourinho will always play with one striker and this will always be Lukaku.
“Of the 126 appearances Rashford has made for Manchester United, I am not sure how many have been in his favoured position as a striker,” he said in his column in The Sun.
“The problem he faces is what can he do about it?
“Yes, he is still very young at 20, but when will his situation change?
“As long as Romelu Lukaku stays fit he is not going to get a starting spot as the lone striker at Old Trafford.
“As long as José Mourinho is the manager, there is not going to be two up top.”
Rashford joined the Manchester United academy at the age of seven and was promoted to the first-team by Louis van Gaal during the 2015-16 season.
He made his debut for United in the UEFA Europa League round of 32, scoring twice against FC Midtjylland in a 5-1 victory.
Three days later, he made his Premier League debut against Arsenal, and again scored a brace in a 3-2 victory at Old Trafford.
He has since appeared 132 times for United and scored 32 goals in the process, but Lukaku’s move to United from Everton in 2017 saw Rashford’s opportunities at striker limited.
José Mourinho’s tenure at the club has seen United predominantly play with one striker as it suits his style of play which aims to restrict the opposition midfield.
Due to Lukaku’s physical attributes and ability to read the game, he can play without support with success and Rashford does not have the size to match the Belgian in Mourinho’s system.
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