Raheem Sterling’s underwhelming start to life in the Eredivisie reached a new low during a disappointing De Klassieker appearance against Ajax. The former England international struggled to impact the game before being substituted early in the second half, prompting a stern reality check from his manager. Robin van Persie has now warned the veteran forward that his fitness and on-field contributions must align quickly to aid Feyenoord's pursuit of Champions League football.Sterling’s search for form at Feyenoord hit a significant roadblock during Sunday’s tense De Klassieker as he struggled to get the better of his marker, Lucas Rosa, before being hooked after just 55 minutes. Having joined the Dutch giants as a free agent following his mutual contract termination with Chelsea in January 2026, the 31-year-old’s once-trademark explosive pace appeared to desert him in the 1-1 draw against Ajax. Although a late Jakub Moder penalty rescued a point, Sterling’s inability to influence the Eredivisie’s showpiece fixture has heightened local concerns regarding his physical readiness to help Feyenoord secure a vital Champions League qualification spot.Following the final whistle, Van Persie was candid about the challenges facing his high-profile recruit, acknowledging that while Sterling is working hard, the club cannot afford to wait indefinitely for him to find his rhythm. The former Manchester United striker admitted that Sterling is still thawing out after a period of inactivity in London but stressed that the demands of professional football remain unsparing. “Those two worlds need to align sooner rather than later,” Van Persie admitted afterwards. “We are working on that, where the most important thing is winning matches during this period of Raheem getting fitter and fitter.“So I do respect and acknowledge where he is coming from, but at the same time we have to deliver as a club. We have to end up second, as simple as that. I believe that he’s making steps in terms of fitness, in terms of what he delivers. At the same time, I want to see more impact off the ball, more impact on the ball.”With Feyenoord trailing far behind runaway leaders PSV Eindhoven, the pressure is on to secure second place and Champions League qualification. This urgency means that Sterling’s adaptation period is being viewed through a microscope, especially given the temporary nature of his stay in the Netherlands. The former Manchester City star is only under contract until the end of the current campaign, leaving little room for a slow burn. Van Persie addressed the situation, stating: "We both agreed that the intentions are really clear. It is a deal until the end of the season; we are both really open for the future and we will see how it goes." Team-mate Moder added a touch of optimism, noting: "Over the rest of the season we will see the best of him, I’m sure."Add GOAL.com as a preferred source on Google to see more of our reportingFeyenoord face a definitive run of fixtures where Sterling’s tactical discipline and physical output will be under intense scrutiny as the club battles to secure a vital Champions League spot. Any further slip-ups could jeopardise their European status and place Van Persie’s position as head coach under further threat during the season-defining sprint in April. Consequently, the veteran forward is effectively on a final audition to bridge the gap in his conditioning and prove he can still compete at a high level before his short-term contract expires.