The Sony Open truly heats up in Miami on Wednesday when Novak Djokovic and Andy Murray square off for a place in the semifinals. It will be the first meeting between the pair since Murray ended 77 years of waiting for Britain and lifted a career’s worth of unimaginable pressure by lifting the Wimbledon title.

Since then, perhaps unsurprisingly, Murray has struggled to replicate the heights reached in dispatching of Djokovic in straight sets on Centre Court. Back surgery in September has meant a slow start to 2014 for the Scot, while further disruption was forthcoming last week when it was announced that he was splitting from the man who played such a key role in getting him over the psychological hurdle to win two Grand Slam titles, coach Ivan Lendl.

Murray has not beaten a player ranked inside the top 10 since that July day in southwest London last year. But there were the first true signs that he had put both his back problems and his breakup with his coach behind him when dispatching of Jo-Wilfried Tsonga in just 74 minutes on Tuesday, incredibly losing just three points on serve.

"I served well throughout the match and just kept putting pressure on him all the time it was his go to serve," Murray, who won the title in Miami last year, said, according to the ATP Tour website. "I made very few unforced errors throughout the course of the match, and that was the difference."

Djokovic lifted the first Masters 1000 title of the year in Indian Wells earlier this month when beating Roger Federer in a final-set tiebreak. Yet, there is a definite sense that Djokovic, too, has not hit top form thus far in 2014. The Serbian was one of the players to follow in the footsteps of Murray by hiring a famous ex-player as coach, but after missing Indian Wells, Boris Becker’s plan to join his charge in Miami has been prevented by having to undergo hip surgery.

Djokovic, who has won three titles in Miami, beat Tommy Robredo in straight sets to reach the quarterfinals.

"[It was a] very solid win," Djokovic of the 6-3, 7-5 triumph. "I made him play an extra shot in important moments and that's why I'm satisfied with the overall match today."

The other men’s quarterfinal on Wednesday will see Roger Federer aim to continue his fine start to the season when going up against Kei Nishikori. It was Nishikori who came out on top when the pair last met, on the clay of Madrid last year, but the Japanese 20th seed will have to battle fatigue having come through a final-set tiebreak, in which he saved four match points, before finally outlasting Spaniard David Ferrer in three hours and six minutes. In contrast, Federer dispatched of Richard Gasquet in just 49 minutes.

There is plenty of intrigue in the day’s two women’s quarterfinals as well. First up will be a repeat of one of this year’s Australian Open semifinals when the supremely talented Pole Agnieszka Radwanska takes on “pocket rocket” Dominika Cibulkova. Radwanska, who lifted the trophy in Miami in 2012, will be looking to avenge her loss in Melbourne having taken the title in Indian Wells.

In the evening session, the woman who beat Cibulkova in the Australian Open final, Li Na, will go up against Caroline Wozniacki. The Dane won the last time the pair met, in 2012, but Li had won the three previous encounters. Both players came through their last rounds in impressive fashion, with Li dropping only two games to Carla Suarez Navarro and Wozniacki only one in ousting Varvara Lepchenko.

Where to watch: Cibulkova and Radwanska will begin the day’s play at 1 p.m. ET, followed by Murray and Djokovic not before 3 p.m. Both matches will be shown on ESPN2. The evening session will then be screened on the Tennis Channel, with Federer up against Nishikori following Wozniacki’s meeting with Li. A live stream will be available from 3 p.m. on ESPN3.