Cristiano Ronaldo could miss Manchester United's top-four showdown with Tottenham on Saturday to ensure he is fully fit for the Champions League.
United host Tottenham at Old Trafford this weekend in a game they must win to get their top-four push back on track after last Sunday's humiliating 4-1 derby mauling at Manchester City.
Ronaldo missed that defeat with a recurrence of a hip flexor problem and flew to Portugal for a mini-break to recuperate, before reporting back for duty at United's training complex on Tuesday.
Although Ronaldo has not yet rejoined full training, he was assessed by United's medical team and undertook a light session, followed by treatment on the affected area from the club's physios.
Ronaldo is desperate to return to action for United against Spurs, but Rangnick and his coaching are weighing up whether it is worth risking the 37-year-old forward from the start on Saturday.
After facing Spurs, United host Spanish champions Atletico Madrid on Tuesday, in the decisive return leg of their Champions League last 16 tie, having drawn the first leg 1-1.
With Edinson Cavani having ruled himself out of the derby with a groin injury that has kept him out of United's last six games, Mason Greenwood suspended and Marcus Rashford short of goals and confidence, interim boss Rangnick has few options to lead the line against Spurs.
But Rangnick and his team are concerned at bringing Ronaldo back too soon and potentially exacerbating his hip problem, which could see them lose him for longer.
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Another fear is that Ronaldo may struggle to recover in time to face Atletico if he plays from the start against Spurs, given there are a little over 72 hours between the two fixtures.
Despite his experience and 15-goal haul this season, Ronaldo has scored just once since the turn of the year and having to lead United's attack, week-in, week-out, has taken its toll on his body.
In the derby humiliation at the Etihad, Rangnick played without a recognised striker, pushing Bruno Fernandes and Paul Pogba forward at times from midfield, but that approach ultimately backfired.
Antonio Conte's Tottenham, who beat Everton 5-0 on Monday and triumphed 3-2 at City last month, are just two points behind United, with two games in hand, in the race for a top-four spot.
