Nadal will now lock horns with Italy's Fabio Fognini for a place in the semi-final of the match. Nadal won 68 percent of his total service points and converted on three of his 19 break points.
In men's singles, top-seeded Nadal entered the quarterfinals in Montreal by beating Guido Pella of Argentina 6-3, 6-4.
The victor past year in Toronto for his fourth title in the event, Nadal won his 380th ATP Masters 1000 match, a day after breaking a tie with Roger Federer for the tour record. They will begin their roles immediately and serve until the end of their existing terms, which run through the 2020 Wimbledon. Fognini stormed into the last-eight of Montreal Masters with a comfortable 6-2, 7-5 win over France's Adrian Mannarino.
"Let's see tomorrow. Another opportunity to be in another final". The victory came in blustery conditions, which Nadal said were not a huge bother. Thiem beat the Russian in April to win the Barcelona title. "On the other side, I played a good match tactically, I played solid from the baseline", Khachanov said.
"I asked Fabio what's going on in his foot because I saw him asking for treatment".
Nadal will play the victor between Gael Monfils and Roberto Bautista Agut in the semi-final on Saturday. He told me about foot pain, which seemed similar to something I have had before, so I was trying to share my experience and what I did then to make it better. He expects Fognini to be in his best form as he is having a great season.
Medvedev claimed a 6-3, 6-3 win over Chile's Cristian Garín in the round of 16.
"It was an up-and-down match, but a positive match for me", Nadal assessed.
Khachanov secured the all-countryman semi by dispatching a lackluster Alexander Zverev 6-3, 6-3.
"I played a great game in the second [set] and he had a bad game in the second game".
Zverev, the third seed and No. 7 player in the world, slammed his racket in frustration in the first set, which elicited a negative reaction from the crowd.
"With all the traveling and short transition, two very tough matches yesterday and two days ago, I think the battery was empty today", said Thiem who won Kitzbuhel on Sunday.