* Guadalajara, Mexico, $50,000+H (Outdoor Hard) : Mirza Basic had a rough start of the season but seems like he is starting to find some form, reaching the quarter-final in Wroclaw and now advancing to the last 4 in Guadalajara.
Mirza toppled the first seed Victor Estrella Burgos 6-3 6-7 6-3 in 2 hours and 2 minutes for his first Challenger semi-final since Tashkent in October. Bosnian player saved all 3 break points he faced to keep his serve intact and he broke his rival once in the 1st and 3rd set to clinch an important win.
Estrella Burgos had two break points in the opening set but he failed to convert them, dropping his serve in game 6 to fall 4-2 behind, unable to recover in the last two return games. They both played well in the second set, saving 3 break points in total to reach the tie break, which Estrella Burgos took by 7-3 to force a decider.
Nevertheless, Basic saved his best tennis for set number 3, never facing a break point and taking rival's serve in game 8, in a pivotal moment of the whole encounter. The 4th seed Jason Jung scored his best result of the season by reaching the semis here, following a one-sided 6-1 6-3 triumph over Mitchell Krueger in 67 minutes, moving to his first Challenger last 4 appearances since Nanchang in September. Both players served under 50% but it was Jung who got the most from his initial shot, losing serve just once and taking 55% of the return points on the other hand.
Krueger failed to find his rhythm, losing serve thrice in a row in the opening set, and despite some better resistance in set number 2, he found himself 6-1 5-1 down in no time at all. He pulled one break back to cut the deficit to 5-3 but Jung served out for the win in game 9, collecting some much-needed points.
Former world number 14 Jerzy Janowicz seems to finally be pain-free, and he already made a great progress in 2017, especially after winning the title in Bergamo Challenger. He stays on a course for crown number 2 after overcoming Tennys Sandgren 6-4 6-2 in 70 minutes. Pole hit just 5 aces but he showed his best tennis for the most important points, fending off all 5 break points and breaking the American thrice for the place in the last 4.
Janowicz's first serve worked like a charm and he was solid on return, just to keep Sandgren out of comfort zone. One break was enough in the first set, Jerzy scored it in game 5 to keep it until the end, and an early break in set number 2 gave him the full control.
Sandgren got broken in game 5 again and that pretty much sealed his faith, with no time for a comeback after that. Denis Shapovalov, one of the most promising youngsters in the world, claimed his first Challenger crown last week in Drummondville, and he reached another semi-final, prevailing against the qualifier Lloyd Glasspool by 4-6 6-3 7-5 in an hour and 41 minutes. As the result suggests, it was a close match but Shapovalom made all the difference with his first serve, facing only 2 break points and dropping serve once.
Glasspool, ranked 415th, did a great job to reach the last 8 as a qualifier and he fought really well, losing serve twice but just falling short in the closing stages of the match. Briton was the better player in the opening set and he scored a lone break in game 9 to clinch the opener by 6-4, leaving the teenager with some work to do in the rest of the encounter.
Shapovalov proved his class right away, losing only 5 points on serve in set number 2 and a break in the second game gave him the lead that he maintained through the set to grab it by 6-3 and force a decider. Canadian continued to serve will in the final set, staying away from troubles in his games and he won 12 out of the final 15 points, including a break in game 11 that propelled him through to the semi-final.
Quarter-final results: Mirza Basic (BIH) vs Victor Estrella Burgos (DOM) 6-3 6-7(3) 6-3 [2:02]
Jason Jung (TPE) vs Mitchell Krueger (USA) 6-1 6-3 [1:07]
Jerzy Janowicz (POL) vs Tennys Sandgren (USA) 6-4 6-2 [1:10]
Denis Shapovalov (CAN) vs [Q]Lloyd Glasspool (GBR) 4-6 6-3 7-5 [1:41]
* Quanzhou, China, $50,000+H (Outdoor Hard) : Quarter-final results: Ilya Ivashka (BLR) vs Uladzimir Ignatik (BLR) 7-6(9) 6-2 [1:39]
Thomas Fabbiano (ITA) vs Steven Diez (CAN) 6-0 6-2 
Maximilian Marterer (GER) vs Yuki Bhambri (IND) 6-3 6-2 
[Q]Matteo Berrettini (ITA) vs Duck Hee Lee (KOR) 6-4 6-7(6) 6-1 [2:00] ALSO READ: Quarter-final results in Challenger Tour: Rublev, Brown, Shapovalov and Auger-Aliassime all reach the last 4