Robin van Persie was left heartbroken after watching his son Shaqueel suffer a serious knee injury during Feyenoord's Europa League defeat to Real Betis. The 19-year-old was stretchered off in Seville just eight minutes after coming off the bench, leaving his father and manager devastated on the touchline as he admitted the "first signs are not looking good" regarding the severity of the blow.What began as a tactical roll of the dice ended in disaster for Feyenoord on Thursday night. Chasing the game against Betis, Van Persie turned to his bench in the 73rd minute, introducing his 19-year-old son Shaqueel to replace the misfiring striker Cyle Larin. The youngster was tasked with salvaging a result, but his cameo lasted just eight minutes before tragedy struck.The atmosphere inside the Estadio Benito Villamarín shifted instantly from hostile to hushed silence when Shaqueel collapsed following an aerial duel. The forward landed awkwardly, his knee buckling under the weight of the impact. It was immediately apparent that the injury was severe; Shaqueel signalled to the bench instantly, unable to put any weight on the leg.As medical staff rushed onto the pitch, the severity of the situation resonated with players from both sides. In a touching moment of sportsmanship, Real Betis winger Antony - formerly of Feyenoord’s arch-rivals Ajax - approached the stretcher to offer a consoling tap to the young striker. Shaqueel was carried off to a standing ovation from the home crowd, a respectful gesture that did little to dampen the sombre mood in the Dutch camp.Because Feyenoord had already utilised all five substitution windows, Van Persie’s side was forced to navigate the final stages of the match with 10 men, compounding a miserable evening in Spain.Speaking after the final whistle, the coach struggled to hide his emotion. The Arsenal and Manchester United legend found himself in the agonising position of managing a professional fixture while witnessing his child suffer a potentially career-altering injury just yards away.As Shaqueel was carried past the technical area, Robin stepped forward to embrace his son, placing a protective arm around his shoulder in a brief moment of fatherly reassurance before the medical team continued down the tunnel."It's not looking good," Van Persie admitted to the press, his face etched with concern. "Tests have to point out how he's doing, but the first signs are not looking good. You hold your heart when any player goes down with an injury. It happened to be Shaqueel today, that's just how it is. You hope for the best, but when you hear the first signs that it isn't, it's heartbreaking."Van Persie acknowledged the difficulty of separating his professional duties from his paternal instincts during such a traumatic incident."I'm a coach, but I'm also his father and I find this terrible," he added. "It's a bit of both. It's heartbreaking that he's going through this. When Shaqueel was carried off the field, I asked how he was doing. I put my arm around his shoulder; that's all you can do at that moment, as a coach and as a father in this case. I just wanted to give him that warmth and the feeling that we're there for him."The injury has sent shockwaves through the Feyenoord squad, casting a shadow over their preparations for Sunday's crucial Eredivisie showdown. Midfielder Luciano Valente expressed the collective pain of the dressing room, noting how difficult it was to watch their manager handle the situation."I find it enormously painful to see him go off like that," Valente said. "Also for the trainer, that is terrible to have to experience."The timing could barely be worse for the Rotterdam giants. On Sunday, Feyenoord face a definitive test against PSV, a match often pivotal in the Dutch title race. Going into such a high-stakes 'Topper' with the squad emotionally bruised and physically depleted presents a massive challenge for Van Persie's management credentials. Van Persie's men are 14 points behind the reigning champions heading into the weekend clash in Eindhoven.Add GOAL.com as a preferred source on Google to see more of our reportingThe club must now wait for the swelling to subside before definitive scans can determine the extent of the damage. However, the language used by Van Persie regarding the "first signs" suggests fears of ligament damage, which could rule the teenager out for the remainder of the season.Shaqueel had been brought on with his team 2-0 down to provide a spark after Larin squandered multiple opportunities to get Feyenoord back into the tie. The 19-year-old has been steadily integrating into the first team under his father’s guidance, making this setback a cruel interruption to his development.For now, the result in Seville - a painful defeat - is secondary. The primary concern at De Kuip is the wellbeing of their young striker, as a father and a football club hold their breath for the medical verdict.