<p>Recent theoretical considerations suggest that preparatory attention mechanisms might play a pivotal role in the anticipation of distractors by proactively suppressing spatial locations and/or specific features. However, this notion stems primarily from studies employing visual search paradigms with simultaneous displays, and recent research using successive displays and isolated distractors challenges this assumption. The efficacy of proactive suppression in setups involving isolated distractors is questioned, underscoring the need for further investigation. The current study seeks to investigate the factors influencing proactive suppression when anticipating isolated distractors in both spatial and temporal dimensions. Across three experiments, we manipulated distractor interference, spatial predictability, and temporal predictability. Results consistently showed that even highly interfering distractors, when fully predictable in time and space, remained difficult to proactively suppress. These findings suggest clear limitations of proactive attentional control mechanisms in the context of isolated distractor anticipation.</p>