"You have to find solutions, you have to find reaction but what you have to find more than anything is the desire and togetherness of a group of players, that they are desperate to perform", Martinez said.
Lukaku entered this summer's World Cup off the back of scoring 27 goals in 51 appearances during his first season at Old Trafford.
Belgium's thrilling 2-1 win against Brazil in Kazan booked the Red Devils a semi-final spot against France in St. Petersburg on Tuesday.
"You have to accept that Brazil have finesse and they will break you down but we did not accept it".
The Belgians may want to adopt that more robust approach from the start against Brazil in order to give midfield maestros Eden Hazard and Kevin De Bruyne time to make decisive passes. "Our finishing was shambolic throughout the World Cup".More news: YouTube stars have died after falling down a waterfall
In the evolving world of worldwide football tactics, Russian Federation 2018 has signalled the return with a vengeance of a system of play that was rendered ineffective by total football four decades ago.
Fred did not play any part in Brazil's World Cup campaign.
"Belgium are young, but they are maturing".
England manager Gareth Southgate, meanwhile, believes that Russian Federation has signalled something of a changing of the guard at the top of the game, with the last two world champions, Germany and Spain, going home early.
After Ronaldo lifted the UEFA Champions League trophy for the third year in a row as Real Madrid beat Liverpool 3-1 back in May, many people were convinced the Madrid star would surpass his Barcelona rival by winning the Ballon d'Or one more time.
The Red Devils entered the semi-finals for only the second time after beating Selecao 2-1 in the quarter-finals. Only Guillermo Ochoa of Mexico, who were knocked out in the round of 16 by Brazil, has had more saves in the 2018 World Cup with 24.