Mohamed Salah's meteoric career could reach new heights on Saturday when his Liverpool team take on Real Madrid in the Champions League final.
The match coincides with the holy month of Ramadan, and Salah, along with Liverpool teammates Sadio Mane and Emre Can, Real Madrid's Karim Benzema and Achraf Hakimi, had faced the decision whether to refrain completely from eating and drinking on the day of the final.
Previously, the likes of former Arsenal striker Marouane Chamakh opted to take a break from Ramadan fasting during matchdays and account for them later in the year. And that option was recently extended to Salah and his Egyptian teammates ahead of the World Cup by Egypt's grand mufti.
Salah -- who set a Premier League record with 32 goals this season, alongside his 11 in Europe -- has been strict to adhere to the Ramadan timetable in the past, according to AS Roma's Director of Performance, as well as fitness coach and performance data analyst for defending World Cup champions Germany, Darcy Norman.
However, Liverpool physiotherapist Ruben Pons says Salah will not fast ahead of Saturday's final.
"We were in Marbella (Spain) and he and Mona (Nemmer), our nutritionist, established a work plan for this week," Pons said.
"He didn't do it (fasting) on Thursday and will not do it on Friday or on game day, so in that sense that is perfect. He (Salah) has been flexible."
Pons, who will be treating Salah while the player competes with Egypt at the World Cup, added to Onda Cero radio: "Salah fasted while we were in Marbella but ate normally on Thursday and he will resume Ramadan after the final. He is very excited, very upbeat and looking forward to Saturday's game."
In his two seasons at Roma, between 2015-2017, Salah "followed the [fasting] rules to a tee," Norman, who closely monitored the striker's hydration levels along with calorie and carb intake during preseason training that fell during Ramadan, told ESPN FC.
Norman would advise Salah and other Muslim players to hydrate as much as possible during non-fasting hours -- including the middle of the night -- and to "eat as cleanly as possible" with "efficient energy sources." That meant avoiding processed foods and binge eating, which can cause digestion problems.
"Momo is the best example [of a Muslim footballer observing his custom]," Norman added, insisting that Roma never got in his way. "You're dealing with somebody's belief system, and I think you have to honour that. If that's what they believe and they can manage their circumstance, then I think you're OK."
Former Ipswich player Nathan Ellington converted to Islam during his playing days. Like Chamakh, Ellington would fast during the month but take game days off. He set up the Association of Muslim Footballers (AMF) in 2012, in part to provide guidance to younger Muslim players.
"There is no conflict between being a professional footballer and being of Muslim faith," the AMF said in a statement. "One just has to look at the success of Muslim footballers -- past and present -- who have prioritised their faith without the need to compromise.
"Over the years, clubs and those involved within the footballing arena are much more aware of Ramadan, and what it entails. Cultural awareness and training within football clubs is much more common, and helped by the ever increasing number of Muslim footballers playing top level football."
Mental strength vs. physical challenge
Although players who fast for long stretches are more likely to suffer on the pitch, the process can boost morale and compensate any negative effects, according to Norman.
"Physically, all the science tells us that there will be a performance detriment," he said. "But then there is the psychological side. If they are a strong observer and they have a very strong faith -- and they feel that it really empowers them or is a big part of who they are and how they operate -- then that can kind of wash out and balance out the loss. It all plays a factor in the outcome."
Getting used to the process is also key. For a first-time faster, feeling light headed or physically weak can leave the player sluggish on the pitch.
"If you're mentally ready to accept it, it makes a massive difference then if you're scared of what your body is telling you," Norman said. "Your body is a very adaptable machine and it just takes time to adapt."
Two-time NBA champion Hakeem Olajuwon said fasting while playing was actually an advantage to him.
"When you are fasting, it's amazing," he told The Guardian. "You feel so light and energetic. Full of energy, that's the way I feel. If you have that mentality that 'I'm fasting, there is no food and I'm tired,' you act that way.
"During Ramadan I think my stats go way up, and I think: 'Wow, I think I may continue to fast throughout the season,' because everything seems like clockwork."
And that opinion is rooted in science too, according to Norman.
"You're definitely lighter because you typically will lose a bit of lean body mass; you're not taking on the calories you need. You are lighter because you are in a dehydrated state," he explained. "And as a result, you feel lighter, you move lighter. These guys are so aware of their body, and whether they are a kilogram or two kilograms heavy or light, they notice a difference."
World Cup impact
Germany is one of several European teams -- along with Belgium, France and Switzerland -- to field a number of prominent Muslim players.
The list reads like an All-Star team: Mesut Ozil, Sami Khedira, Ilkay Gundogan and Antonio Rudiger of Germany; Paul Pogba and N'Golo Kante of France; Marouane Fellaini, Adnan Januzaj and Nacer Chadli of Belgium. Mane, meanwhile, will represent Senegal in Russia.
It is unclear whether any of those players will fast during the weeks leading up to the tournament. However, Saudi Arabia, Morocco, Egypt, Iran and Tunisia will all field World Cup teams consisting almost entirely of Muslim players brought up in countries where Ramadan fasting before training at night is the norm.
Egypt boasts several European league players including Arsenal's Mohamed Elneny -- a devout Muslim who fasts and prays five times a day -- and promising winger Mahmoud Hassan. But it is Salah and his 33 senior international goals that give Egypt a fighting chance in the tournament.
Ramadan is set to end during the first days of the World Cup -- regions observe the dates on different days depending on the sighting of the new moon so there is a risk of overlapping with Russia's opening match against Saudi Arabia on June 14, or the following day's games featuring Morocco vs. Iran and Egypt vs. Uruguay.
But should Salah choose to fast during his World Cup training, Norman does not anticipate that the PFA Player of the Year will lose a step.
"Nothing really shakes him, he's a very positive guy," Norman said, citing Salah's unparalleled work ethic at Roma. "He's an unbelievable professional, and unbelievable person."