The 26-year-old has been retained in Gareth Southgate’s squad for the forthcoming fixtures with Croatia and Spain.
His club manager Jokanovic, however, has reminded him of the fact he has conceded 11 goals in the five appearances he has made so far this season, for which Jokanovic also recruited Fabri and loanee Sergio Rico as potential alternatives.
Fabri started the season as Fulham’s first-choice and Rico has also had a chance to impress, providing Bettinelli with significant competition, and Jokanovic said: “He needs to improve.
“He needs to make the step forward like other parts of the team. It’s simple – he can be satisfied with the call-up.
“I had a question before about the number of goals conceded at Fulham – he must be hurt and I can’t give you another answer.
“Congratulations for this call, I believe he can make a better job than what he’s made now, (but) it’s not just Marcus, I am talking about all the players.
“The English national team and Southgate made his choice, I will make mine and what I try for my side is to encourage all the people to push forward, like Marcus too.”
On Sunday Fulham host Arsenal, who have won eight successive matches in all competitions, and Bettinelli is expected to retain his place.
Jokanovic, from Serbia, also predicted that Ryan Sessegnon could soon be in the England squad.
He added of his goalkeeper’s call-up: “It’s good for experience and himself to feel important, but this job never stops.
“After the break, or before they go to play for national team, it’s a really important game for us (against Arsenal) and he must be focused for the job here and when he goes there he needs to do a job for the national team.
“The benefit (of competition from Fabri and Rico) is similar. They are good players and a similar level.”