India could find no way past Trott, who finished unbeaten on 66 out of 161 for three as England dug in to try to close out a stalemate in pursuit of a famous series victory. The tourists reached stumps with a lead of 165 and high hopes they will be able to keep India at bay again long enough to ensure a draw here and therefore a 2-1 overall success.
Trott's survival - where Ishant Sharma and Mahendra Singh Dhoni were convinced they had him caught-behind, only for umpire Kumar Dharmasena to disagree - was aggravating for India, but for Ravichandran Ashwin, the bonus four beforehand was most annoying. And he said: "It's just the shot that he got away from that rolling ball. It just seemed to be ridiculous."
He added: "If it didn't seem ridiculous to you ... it did to us. But nothing got out of hand."
Trott was key on day four, and may well be again on day five when Alastair Cook's team will be seeking an achievement which has proved beyond all others for England since 1984-85.
Their number three was also at the centre of three flashpoint incidents as India became increasingly antagonised by events at the VCA Stadium.
There appeared to be some general amusement over the first, when Trott took advantage - as the Laws of Cricket entitle him to - by hitting a stationary ball for four from well out of his crease, after a delivery slipped from Ravindra Jadeja's grasp and trickled to a standstill two-thirds of the way down the pitch.
Lengthy expressions of discontent followed, towards both Trott and the officials, and at one point the batsman responded by mouthing a cheeky kiss towards Ishant from under his helmet grille.
Finally, deep into the evening session, Ashwin was exasperated by Trott backing up too far at the non-striker's end and stopped in his delivery stride to warn he could run him out. The off-spinner made it clear after close of play that he, for one, did not see the funny side.
"I can run him out if he can hit that ball," Ashwin said, a reference to Trott's boundary off Jadeja. "He said 'run me out then'. I said I wouldn't."