The duo are in the midst of miserable campaigns at club level, having failed to make a Premier League appearance – at Leicester City or Watford respectively – since the start of the season.
Musa has started just once for the Foxes – scoring in the League Cup victory over Sheffield United – while Success was barely considered during previous Hornets boss Marco Silva’s time as coach, making one cameo appearance in the same competition.
The latter also endured injury problems towards the end of 2017, but despite appearing to be outside bets for the Super Eagles’ World Cup squad, Rohr has insisted the duo could still make the cut if their fortunes improve before the trip to Russia.
“Everything depends on their recovery, if they re-establish themselves or not,” the German coach told KweséESPN. “If they play in their clubs or not.
“It depends on their form at the moment when we make the list,” he added, “and that’s only in May – mid-May – that we have to produce our provisional (squad) list.”
Former Nigeria first-choice Musa has struggled to make an impact at King Power Stadium since moving from CSKA Moscow for £16.5m in 2016, but salvation could be on the horizon in the form of a loan move back to his previous club.
The 25-year-old shone at the last World Cup – scoring twice against Argentina – but netted just twice in 21 top-flight outings last term.
“I will take the players who are the most in form,” Rohr said.
The former Gabon coach is currently in Morocco where he is overseeing the home-based Super Eagles’ encouraging African Nations Championship campaign.