Grigor Dimitrov staved off match point against Feliciano Lopez to claim his first-ever grass court title at the Queen's Club Aegon Championships.
The 23-year-old ground his way to a gritty 6-7 (8-10) 7-6 (7-1) 7-6 (8-6) victory over Spaniard Lopez, for his third title of the season and his career.
The fourth-seeded Bulgarian claimed glory and the £74,654 winner's purse, converting his second match point in the final-set tie-break.
Highly-rated Dimitrov has long been tipped for a grand slam-winning future and he can now attack Wimbledon with increased hope.
Toledo-born Lopez had been chasing a follow up to his 2013 title at Eastbourne - one that he will defend next week.
The 32-year-old was unable to deny Dimitrov, though, the Bulgarian cheered on again from the stands by girlfriend and five-time grand slam winner Maria Sharapova.
Lopez claimed the first set at the fourth opportunity from the tie-break, before Dimitrov finally found some poise to save the contest.
Dimitrov's serve came under pressure in the 12th game of the second set, with Lopez claiming an advantage to have the title one point from his grasp.
Just as the 32-year-old was eyeing glory, though, Dimitrov salvaged the game and a second-set tie-break.
This time Dimitrov emerged victorious, and in defiant fashion too.
The 7-1 victory ought to have ensured a reversal of fortunes strong enough to guide the Bulgarian home; instead stubborn Lopez clung on for yet another tie-break.
The tightly-matched duo claimed one break apiece in the final set, before Dimitrov finally took control.
After wasting one match point in the tie-break Dimitrov finally claimed the title, Lopez blasting a stray forehand into the net.
Dimotrov had dispatched top-seed Stan Wawrinka in the semi-finals and will prove a popular champion in Kensington.
Britain's 24-year wait for a doubles champion at Queen's continues after Jamie Murray and John Peers were unable to topple second seeds Alexander Peya and Bruno Soares.
Scot Murray and Australian Peers lost their fourth consecutive clash with Austrian Peya and Brazilian Soares, losing the champions' tie-break in a close-fought encounter.
Murray and Peers claimed the first set 6-4, and broke the tournament second favourites in the first game of the second set.
Their seasoned opponents fought back to square the tie, taking the second set 7-6 (7/4), to tee up the decisive first-to-10 tie-break, played in lieu of a third set.
Peya and Soares won out 10-4 to claim the title, leaving 28-year-old Murray deflated not to convert such a promising start.
Jeremy Bates remains Britain's last doubles title-winner at the Queen's Club Aegon Championships, back in 1990.
Neil Broad made the final in 1993, and Murray had impressed in being the first Brit to follow suit.
Murray and Peers saw off top seeds Bob and Mark Bryan en route to the final, but were unable to repeat that giant-killing when silverware was on the line.
Murray and Peers had lost three consecutive matches against Austrian Peya and Brazilian Soares, including a clash at the US Open.