Sevenoaks Town are still unbeaten in 2019, but not without a few scares.
Two-nil down after only nine minutes, they battled back to level by half-time - only to concede a third soon after the restart.
Oaks then hit back again to restore parity and both teams had chances to win the game in the last half hour.
Boss Micky Collins gave new signings Tommy Whitnell and Luke Holness their first starts, while Mikey Dalton replaced suspended Dan Parkinson.
Whitnell, signed from Tonbridge Angels, marked his full debut with the second goal in between two Frankie Sawyer strikes.
Oaks made a shaky start - Grinstead striker Matt Day charging down goalkeeper Ben Bridle-Card’s attempted clearance inside the first minute.
Sixty seconds later the West Sussex side were in front, former Oaks player Jerson Dos Santos heading in via a post from a corner.
Greg Cundle doubled the lead four minutes afterwards, following a quick break leaving Oaks up against it.
Sawyer pulled one back around the half hour popping up at the far post to head in left back Ryan Makhosini-Khanye’s corner.
Whitnell made it 2-2 in stoppage-time, finishing well from Ryan Fowler’s set-up, giving Oaks the perfect boost at the break.
However Grinstead again started the second half well, Day putting them in front as the hosts failed to defend a free-kick.
Sawyer then added his second, taking advantage of slack marking to get his eight minutes later.
Grinstead hit the woodwork, the ball bouncing off a post and back into the hands of Bridle-Card who also pulled off a fine point blank save to keep things level.
Oaks also went close - Josh Dorling missed out at the far post, Fowler fired wide, before
Makhosini Khanye curled his free kick inches wide late on.