The Prestonpans puncher extended his professional record to 13 straight wins as he barged his way to the front of the queue to take on WBC super lightweight champion Jose Ramirez.
The clash at Glasgow’s SSE Hydro was a final eliminator to face the American and there was no chance Taylor, 27, was going to let his opportunity slip.
He had to put in a disciplined display against the Ukrainian - himself a former world champion - but the Scot made his mark in the 10th round as he knocked Postol to the floor with a perfectly-timed left hook.
And his efforts were recognised by the judges, who scored him the victor by a handsome 118-110, 117-110, 119-108 margin.
Taylor’s promoter Barry McGuigan admitted before the fight he had gambled by throwing his man - second in the WBC’s ranking - in with the number one contender.
The thinking was that victory would provide a fast-track route to a title shot but there is no doubt Taylor belongs among the elite.
Yet the respect Taylor had for his opponent was clear from the opening as he resisted throwing any wild shots that might hand Postol an early gift.
The 27-year-old, though, is never one to hang around and the southpaw sent out a warning with a couple of big rights in the second round.
Pound-for-pound king Terence Crawford is the only man to have ever beaten Postol and the Iceman refused to be ruffled when Taylor connected with another thudding left hook in round three.
When the Scot caught him off-guard as they broke from a clinch, a quick shake of the head was the only mere hint of frustration.
Postol was bundled to the floor early in the fourth but referee Ian John Lewis ruled it a slip. He responded with a series of jabs that did enough to quell Taylor’s aggression.
But Taylor has learned from last year’s bout with Miguel Vazquez where his impatience almost cost him. Working his own jab well, he waited for the openings where he could land to the body.
Taylor was forced to put his gloves on the floor at the start of the seventh as Postol reigned blows down but again Lewis refused to sanction the knock-down as he signalled Postol had held Taylor’s neck down.
Postol was getting through the Edinburgh fighter’s defences with increasing regularity, but a well-placed right to the body was Taylor’s response as the eighth got underway.
A brief trade-off at the end of the stanza brought a round of appreciative applause from the Glasgow crowd.
And Taylor’s faithful were off the seats again in round nine. A double jab forced Postol back and there were further decent shots as the home favourite got through with a powerful left hook and a smart three-punch combination.
And having sapped Postol with numerous crunching body shots during the 10th Taylor got the breakthrough he was looking for as he sent a left hand over the top to send his opponent tumbling backwards.
The 34-year-old survived the count and came back with a quick-flash flurry that momentarily dazed Taylor, but he closed out the contest in confident manner.
Speaking after the fight, Taylor said: “I feel I’m on the verge of fulfilling my dream and fighting for a world title.
“That was playing on my mind a little bit before the fight. I didn’t feel any pressure but it was playing in the back of my head that if I won, I’d be fighting for a world title.
“However, I felt I dealt with that well. It was a little bit of a below-par performance. I started very poorly in terms of defence and switched off too much.
“But I adapted and I definitely think I can be 20 or 30 per cent sharper. I’m happy enough, though, and the next one will be the big one.”
Earlier in the night Congolese-born heavyweight Martin Bakole made quick work of defending his IBO Continental Heavyweight strap.
Bakole, now based in Airdrie, sent Kent’s DL Jones to the canvas twice inside the opening 62 second before the contest was waved off.
And Edinburgh’s Lee McGregor claimed the IBF world youth bantamweight title with a fourth-round stoppage of Tanzania’s Goodluck Mrema.