Andy MURRAY qualified for the Australian Open final for the fourth time after a night of thrilling drama on Rod Laver Arena in Melbourne.
In a highly-charged contest with the giant Czech power merchant Tomas Berdych, Murray proved that he is not just a world-class tennis player, but a pretty good agent provocateur as well.
There is nothing like a grudge to liven up the often antiseptic world of modern tennis and Murray was clearly feeding off a private grievance.
Private in the sense of personal, that is, rather than secret. For everyone throughout tennis knows that there is ill feeling left over from the departure of Murray's former assistant coach Dani Vallverdu in December, which was followed by Vallverdu's subsequent appointment as Berdych's head coach.
It still came as a surprise, though, to see Murray show his feelings so openly on the court.
The match came alive with emotion after the ninth game, in which the Scot stymied Berdych's attempt to serve for the opening set and then aimed his celebration straight at Vallverdu, who was sitting in Berdych's courtside box.
A few wags on Twitter suggested that this might have been simple force of habit, yet those close to Murray stress that he has drawn huge motivation over the past couple of months from the upheavals in his camp.
To get a chance to prove a point against Berdych and Vallverdu in the first Grand Slam championship of the year is exactly what he would have wanted.
There was an electricity on the court from the beginning. In fact, it was almost as if both players wanted this win too badly. They were playing urgently, but stiffly, and the error count was escalating on both sides of the net.
So too was the interpersonal drama as Berdych responded to Murray's pointedly targeted celebrations with a death stare at the change of ends.
At the end of a gruelling 76-minute opening set, Berdych managed to snatch the decision on a tiebreak, and then said something as the two men crossed underneath the umpire's chair.
Murray complained to Pascal Maria, the man in that chair, that "he's talking to me", whereupon Maria asked Berdych what he had said.
"Good play, Tomas - that's all I said," came the reply.
All very childish, but still significant in the way that the match played out, for suddenly Murray found a streak of pure hitting and his opponent vanished from the contest for the next half-hour.
Berdych is known for being self-contained on the court, and the sense of confrontation seemed to unsettle him more than Murray.
Murray needed just 30 minutes to level the match with a bagel set - the first set that Berdych had dropped in the whole tournament.
The pressure was now all reversed on to the Czech and he went on to help Murray out with a number of double faults that led to a single break of serve in each of the third and fourth sets. That was enough, given how well Murray was defending his own serve, to make the difference in a 6-7, 6-0, 6-3, 7-5 scoreline.
Speaking to Jim Courier on the court straight after his victory, Murray admitted that the first set had been animated by a little extra tension because of the coaching triangle, yet insisted that it was "unfair" how much had been made of Vallverdu's role in the build-up to the match.
Later, in the interview room, he expanded on this point and claimed that "you guys (the assembled media) wanted there to be tension. I sat in here the other day and got asked more questions about Dani than I did about the match I just played".
Even his fiancee Kim Sears seemed to be drawn into the subplot at courtside, judging by the television cameras that caught her delivering some uncharacteristically uncouth remarks .
Sears' outburst came after Murray had broken serve when Berdych served for the first set at 5-3. Lip readers suggested that Sears had shouted out: "F*****g having that, you Czech f*****g f**k".
The PA announcer had earlier played a few bars of The Gambler in honour of the presence of country singer Kenny Rogers, but perhaps Tammy Wynette's Stand By Your Man would have been a more appropriate choice.
(© Daily Telegraph, London)