@JeremyECrawford can an attack of opportunity be used to make a grapple or a shove?
— Jon Carroll (@Joncarrollwrite) August 14, 2015
Grappling/shoving are part of the Attack action (PH, 195). Take the Ready action to grapple/shove outside your turn. https://t.co/NzAXyieuMH
— Jeremy Crawford (@JeremyECrawford) August 14, 2015
Battlemaster manouver could be a solution to add some control outside your round.
Sentinel feat could work, too.