Verdasco enters Qatar ExxonMobil Open quarters 

Doha, Qatar: Lean and strong and fit and hungry, Fernando Verdasco showed he has plenty still left in his tank.

The 36-year-old showed that his shots, especially the forehand, still pack plenty of punch and overcame a lapse in concentration that cost him the second set to beat Serbia's sixth seed Filip Krajinovic 7-5, 4-6, 6-0.

Verdasco, who is a Doha resident since 2016, fired 17 aces and had firm control in the match right from the start, but momentarily it looked like he was losing his concentration towards the end of the second set.

But the Spaniard came back with all guns blazing in the third and did not give Krajinovic any chance.

The former world No.7 had earlier said that he would help Qatar improve in the sport.

“My friends in Doha, before I came here, were telling me to move here, to help sport and help the country become better in sport. So I thought, why not?” Verdasco said. “I'm at an age already in my career that I have to start thinking – still hopefully playing tennis for a few more years, but obviously my career is going to come to an end somehow, someday.

“I think that Doha is the place for me that, after my career, I can really help the country to become better in sport. I think that this country is improving amazingly in that way, making huge events. Hopefully in the future, after I finish playing tennis, I can have a spot in Qatar in sport and help the country to become even better and bigger.”

Verdasco will meet Corentin Moutet in the quarterfinals, after the 20-year-old Frenchman shocked fourth seed Milos Raonic 7-6(7-4), 7-6(7-4).

Big serving Raonic fired 13 aces, but Moutet, who came through the qualifiers, held his nerve in the tie-breaks for a famous victory.

Third seed Jo Wilfried Tsonga was also dumped out in the round of 16.

The veteran Frenchman, who was the champion in Doha in 2012, put in an error-strewn performance to go down 6-7(9-11), 1-6 to Serbian Miomir Kecmanovic.

Tsonga, who had to call his trainer to the court after suffering a stiff back, had plenty of chances in the first set tie-breaker before handing it to his 20-year-old opponent with back-to-back unforced errors.

It was all Kecmanovic in the second set and the Next Gen player grabbed his opportunity while Tsonga looked well and truly beaten by then.

"It was definitely one of my better wins. You know, I've had some exciting wins last year. And to start the year off with such a big name, it's definitely motivating me and giving me a lot more confidence to keep going," said Kecmanovic.

Kecmanovic will take on Marton Fucsovics in the quarterfinal after the Hungarian defeated Turkey's Cem Ilkel 6-1, 6-4 in the round of 16.

Earlier, Russian Andrey Rublev put in an impressive show as he breezed past Kazakhstan's Mikhail Kukushkin 6-2, 6-2 to book his berth the quarterfinals.

Rublev, the runner up in 2018, converted four of his nine service breaks to ease through his first match of 2020.

"I'm really happy that I could win in straight sets today," said second seed Rublev. "I think it was more of a mental match. Both of us was not really feeling the ball as normally we can feel, so it was more about mental."

The 22-year-old World No.23 will play Pierre-Hugues Herbert for a place in the semifinals.

Frenchman Herbert booked his place in the last eight with a 6-1, 6-3 victory against Serbia's Laslo Dere.