(a) Mass growth and (b) semimajor axis evolution of plan-etesimals in a ring located at r = 0.3 AU. Each line represents one planetesimal and red dots indicate planetesimal-planetesimal collisions. Gray lines represent all planetesimals in the simulation. The yellow and blue lines correspond to the bodies that finally reach the pebble isolation mass, and those that fail to reach the pebble isolation mass but grow above 10⁻² M_⊕, respectively. The green horizontal line represents the time that large planetesimals start rapid pebble accretion. The mass growth is rapid at close-in orbits for both pebble and planetesimal accretion.