Pictured: Zachary Svadja, Tiburon Challenger.
Zachary Svajda (USA) def  Ben Shelton (USA) 2-6 6-2 6-4
19-year-old American Zachary Svajda has burst onto the tennis scene, after claiming his maiden ATP Challenger title in California.
After needing deciding set tiebreaks to close out his opening two matches, Svajda found form and managed to reel off another three wins to lift the trophy.
In an all-American clash on Sunday between two touted youngsters, the 19-year-old ruined the 20th birthday of his counterpart, playing the more consistent baseline game.
Shelton has now reached three Challenger finals since July but has been unable to convert one into a title.
Meanwhile, Svadja is yet to lose a professional final, and consequently, will see his ranking rise over 100 places to a career-high 255.
Gwangju, South Korea
 Zsombor Piros (HUN) def  Emilio Gomez (ECU) 6-2, 6-4
22-year-old Zsombor Piros has won his second ATP Challenger singles title, taking out the 80K event in South Korea.
Piros, who claimed the Australian Open Boys singles title in 2017, has now been victorious on clay and hard courts at this level, after triumphing in Finland earlier this year.
The Hungarian overcame Aussies Li Tu and Rinky Hijikata, as well as fourth seed Christopher Eubanks on his way to the final, before proving too consistent for top seed Emilio Gomez in the decider.
On the back of his successful week, Piros will rise 22 places in the ATP rankings to a career-high number 138.
Australian Marc Polmans was also in Gwangju action, competing in just his third tournament since February.
The 25-year-old fought his way to the semifinals, before bowing out to top seed Gomez in a deciding set tiebreak.
Nonetheless, a strong week will see Polmans rise over 200 places in the ATP rankings to world number 562.
Mouilleron le Captif, France
Jelle Sels (NED) def Vasek Pospisil (CAN) 6-4 6-3
27-year-old Jelle Sels has won his first Challenger singles title, defeating former top 25-ranked Canadian Vasek Pospisil in the final.
In front of a packed crowd on France’s West coast, Sels managed to hold his own serve whilst breaking Pospisil’s, on the back of his dominant forehand and ability to attack the net.
The Dutchman, who had previously won five ITF titles at 25K and futures level, will receive a major rankings boost on the back of his Challenger triumph.
After beginning the week at world number 173, Sels will now move inside the ATP top 150 for the first time – at a live ranking of 141.
Timofey Skatov (KAZ) def Jozef Kovalik (SVK) 7-5, 6-7(2), 6-4
21-year-old Timofey Skatov has claimed his maiden ATP Challenger title at the 125K event in Italy.
Skatov was gifted a kind draw for an event of this level – facing no players inside the ATP top 120 – but took full advantage to lift the trophy.
The Kazakhstani, who qualified for his first Grand Slam main draw at this year’s Australian Open, overcame Jozef Kovalik in a tight final which lasted more than three hours.
In a series of extensive clay-court rallies and after an unfortunate match point double fault, the 21-year-old prevailed for the biggest win of his career.
Skatov will enjoy a big rankings boost, rising from 209 to a career-high world number 151.
 Lukas Klein (SVK) def Nick Hardt (DOM) 6-3, 6-4
24-year-old Lukas Klein won his second ATP Challenger title on Alicante’s hard courts, dropping just one set from his five matches.
Klein overcame Nick Hardt in Sunday’s final, who was competing in his maiden final at Challenger level.
The Slovakian capitalized on his serve to take control of the match on his way to a comfortable straight-sets win.
Klein, who sat at world number 328 in May, is now up to a live ATP ranking of 180.
[Q] Jan Choinski (GBR) vs  Juan Pablo Varillas (PER)
World number 457 Jan Choinski came through qualifying to reach his first ATP Challenger singles final since 2018 at the 80K event in Brazil.
Second seed Juan Pablo Varillas also eased his way into the decider without dropping a set, in search of a fifth Challenger title.
Before play was interrupted due to rain, Choinski, a 26-year-old competing for Great Britain, led Varillas 6-4, 2-3* – closing in on a maiden title at the level.