Rafael Nadal attains new personal best after defeating Stefan Kozlov at the Mexican Open

Rafael Nadal has enjoyed his best-ever start to a season, with a 12-0 win-loss record after defeating Stefan Kozlov 6-0, 6-3 in the second round at the Mexican Open on Wednesday.

The Spaniard entered the match after a comprehensive win over Denis Kudla, while Kozlov beat Grigor Dimitrov in a tightly-contested match despite dealing with severe cramps in the second and third set.

However, the 35-year-old Spaniard produced a dominant display from the very first game and his intensity was hard for Kozlov to cope with. The King of Clay cruised through the opening set to take it 6-0 and maintained his intensity in the second. Kozlov did have a few moments in the match, producing some good winners and breaking the World No. 5 in the second set.

However, the match was the Spaniard's to lose and he won the second set 6-3 to book his place in the quarterfinals of the tournament.

With this victory, Rafael Nadal has now won 12 matches in a row this year, thus marking his best-ever start to a season. The Spaniard surpassed his previous best, which was 11 in 2014. That year, his winning streak came to an end at the hands of Stan Wawrinka in the Australian Open final. He also improved his Acapulco record to 22-2 with all of his wins coming in straight sets.

Rafael Nadal takes on Tommy Paul in the quarterfinals

Rafael Nadal faces Tommy Paul in the quarterfinals in Acapulco

The Spaniard's next opponent is another American, Tommy Paul. The 24-year-old beat fifth seed Matteo Berrettini in the first round after the latter retired due to an abdominal injury. He then defeated Serbia's Dusan Lajovic in three sets to seal his place in the quarterfinals.

Rafael Nadal and Tommy Paul will meet for the very first time when they lock horns in Acapulco and the winner faces either top seed Daniil Medvedev or Yoshihito Nishioka in the semifinals.

The Russian, who has a chance of becoming the new World No. 1, reached the last eight with little trouble as he breezed past Pablo Andujar 6-1, 6-2.

Elsewhere in Acapulco, sixth seed Cameron Norrie booked his place in the quarterfinals after coming back from a set down to beat John Isner. He faces Peter Gojowczyk, who received a bye to the last eight following the withdrawal of Alexander Zverev due to unsportsmanlike behavior.

A rematch of this year's Australian Open final is very much on the cards as Nadal and Medvedev should be able to beat their respective opponents in the quarters.