The second half was less spectacular with van Velzen and Liam Wilson trading attempts before Lawrence's cheeky chip lacked direction after a James Wilson lay-off.
Brandon Moores forced a smart save out of Gollini but Garratt bettered it at the other end by diving to keep out Rothwell's bending drive. Van Velzen turned to hammer a speculative volley just wide but the hosts managed some late pressure and, after Paris Bateman had the ball in the net when the whistle had sounded, captain Joe Guest belted a long-range piledriver past Gollini to reduce the deficit seconds before the end.
United: Gollini; Grimshaw (Wilkinson 74), Ioannou, McCullough, Blackett; Rothwell, Ekangamene (Rudge 69), Pearson, van Velzen; Lawrence (Gorre 74); Wilson. Sub not used: Coll.