Critical scholarship in sport for development (SfD) advocates transformative research to disrupt the historical colonising view of sport as a vehicle to acculturate people into the values and norms of dominant Western culture. Youth participatory action research (YPAR) involves youth throughout the research process and consequently has the potential to challenge hegemonic forms of knowledge production in SfD. In reality, however, authentic engagement of co-researchers in the research process is often largely confined to data collection. This article draws on the decolonising lens as a theoretical framework to examine tensions, possibilities, and power relations that researchers and co-researchers encounter when co-designing and implementing YPAR in SfD. The project comprised a sixteen-week YPAR in a community-based football programme in Melbourne, Australia. Data collection comprised weekly collaborative meetings, observations collected as field notes, artefacts produced by participants, interviews, and reflective meetings. Findings centred on three themes: (a) finding sensitive ways to navigate the tensions of building trust and rapport; (b) negotiating the struggle between the co-researchers and the coaches about the use of space within the sport context; and (c) the challenges of relinquishing power in research and knowledge production, as reflected in our collective struggle to communicate to participants the value of YPAR for themselves and their communities. The findings challenge a romantic view that YPAR is guaranteed to be an empowering experience for young people; instead, they foreground the complexities and messiness of the process of sharing power with co-researchers in SfD. We conclude by advocating for critical, reflexive YPAR with explicit social transformation objectives to work toward the co-production of knowledge with young people.