<p>While knowledge construction (KC) and group-level regulation are known to be critical for successful collaborative problem solving (CPS), the dynamic interplay between them remains underexplored. To capture the complex KC-regulation interplay, this study examined the sequential and temporal patterns of KC and group-level regulation during a four-week CPS task. Video data from 24 undergraduate students in six teams were coded and analyzed using process mining to visualize and compare interaction flows across high-, mid-, and low-performing groups. Results showed that KC was frequent across all groups, but performance differences were explained by how regulation was temporally positioned within epistemic activity. High-performing groups selectively embedded regulation within epistemic sequences. The groups used socially shared task understanding as a bridge back into sustained knowledge construction and maintained reciprocal cycles that returned to elaborative KC. In contrast, mid- and low-performing groups showed truncated or locally confined regulatory loops that were weakly reintegrated into KC. Performance gaps were most pronounced during the solution ideation phase, indicating that regulatory effectiveness is phase-sensitive in extended CPS. These findings contribute a process-oriented account of KC–regulation interplay and inform the design of phase-sensitive supports for collaborative learning.</p>