Gloucestershire resumed on 279-7 but quickly lost Todd Murphy without scoring and Ajeet Singh Dale for two, as Van der Gugten twice found the edge.
Bracey farmed the strike effectively and punished the odd bad ball with the second batting point coming up in the 104th over, while Archie Bailey finally got his first Championship runs in his fifth match and third innings to earn a few cheers.
Bracey was dropped at deep mid-wicket on 87 off Van der Gugten, and that proved costly as he moved to a third century of the season.
Glamorgan’s frustration grew as fielders moved in and out, Bailey (19 not out) increased in confidence, and Bracey laid about him hitting 13 fours and four sixes, before lofting Crane to long-off.
The economical Ajeet Singh Dale made the first visitors’ breakthrough in scorching afternoon heat as Zain Ul Hassan hooked to fine leg on nine, while Asa Tribe looked in good shape for 35 before edging Bailey to Bracey.
Bailey then induced Kiran Carlson (14) to flick to fine leg, while Sam Northeast (48) seemed on the way to a big score before left-arm spinner Graeme van Buuren got one through his defences to nudge one bail off to the batter’s bewilderment.
At 121-4, Glamorgan had work to do as the ball went soft, after some self-inflicted damage.
Ingram and Kellaway applied themselves studiously in the evening session, despite the dual distractions of hundreds of swooping gulls, and the distant strains of Oasis sound-checking at the nearby Principality Stadium.
Kellaway reached his half-century off 83 balls with seven fours, while Ingram passed the landmark off 103 balls in the final over, but Glamorgan were content to see out the day without too much aggression against some tidy bowling.
