Bosnia are level with Greece, 1-0 winners over Slovakia, on 22 points from nine games but with a vastly superior goal difference (+23) over their rivals (+6) before the final round of qualifiers on Tuesday.
Bosnia visit Lithuania while Greece are at home to Liechtenstein in the climax to their neck-and-neck race for an automatic berth in next year’s finals in Brazil.
“It would be a disaster if we failed now and I am convinced that we will get the win we need in Kaunas,” Bosnia coach Safet Susic told state television BHT after his side scored four times in a frantic 12-minute first-half spell.
“We never doubted we would pick the lock. It was a question of time, and once we scored there was no stopping us from celebrating an emphatic victory.
“I told the players to slow down in the second half in order to avoid bookings and injuries.”
Edin Dzeko scored twice and Zvjezdan Misimovic and Vedad Ibisevic added the other two for Bosnia, who were treated to a standing ovation by their noisy fans after the final whistle.
Beaten in the reverse fixture 8-1 a little over a year ago, Liechtenstein held out for 27 minutes in a packed Bilino Polje stadium before Manchester City striker Dzeko opened the scoring with a downward header after a perfect cross from the right by Misimovic.
The midfielder turned scorer seven minutes later when he drilled in a crisp shot from 12 metres before Ibisevic and Dzeko netted inside a minute to send the home fans into raptures.
Stand-in right back Avdija Vrsajevic tormented the visitors with darting runs on his flank and his pinpoint deliveries set up Misimovic and Ibisevic for the second and third goals before Dzeko netted the fourth after a flowing team move.
Liechtenstein keeper Peter Jehle produced several fine saves early in the second half before Nicolas Hasler pulled one back on the hour for the visitors, steering in a shot off the crossbar.
The home side took their feet off the gas in the final third of the match, although Misimovic came close with a curling shot from the edge of the penalty area.
“We have made one of two steps towards the finals and it’s now up to us to finish the job in Lithuania,” Ibisevic said.
(Writing by Zoran Milosavljevic, Editing by Sonia Oxley and Stephen Wood)