Former world number one Rafael Nadal has been enjoying his tennis again in 2017. The Spaniard's victory over ninth seed David Goffin in the quarterfinals of the Mutua Madrid Open has meant that he has overtaken Australian Open champion Roger Federer at the top of the race to London.

The four-time Mutua Madrid Open champion lost to Federer in the final of the Australian Open in five sets, in the fourth round at Indian Wells and in the final of Miami Open. Nevertheless, Nadal's clay court form has been exceptional as the 14-time Grand Slam champion claimed his 29th Masters 1000 title at the Monte Carlo Rolex Masters and tenth title at the Barcelona Open, and currently is on a 13-match winning streak.

Nadal's quest for a fifth title at the Caja Magica is in serious jeopardy as the Spaniard will be competing against second seed and defending champion Novak Djokovic. The Serb has defeated Nadal in their last seven consecutive meetings with Nadal's last victory over Djokovic coming in the final of the French Open in 2014.

Despite, having the edge over the Spaniard in recent years, Nadal will be the slight favourite purely based on recent form. The 12-time Grand Slam champion is competing in just his second semifinal of the year. Djokovic suffered a second-round exit at the Australian Open, Nick Kyrgios defeated him twice in Acapulco and Indian Wells, and Goffin edged past him in Monte Carlo last month. Nevertheless, there has been some glimpses of Djokovic's best form this week in Madrid as he looks to retain his title.

Nadal's route to the semifinals

The four-time champion had a bye in the first round, and he had been suffering from an ear infection, which delayed his start to the tournament. The fourth seed was supposed to play his second round match with Fabio Fognini on Tuesday but the tournament gave him an extra day to rest. It was a difficult tussle for the Spaniard, who wasn't pleased with how he played but he won the match, which he might have lost in the last two years.

Nevertheless, Nadal defeated the Italian in three sets, just three minutes shy of three hours. The Spaniard's performance in the third round against 16th seed Nick Kyrgios was impressive, and he crushed the Australian, 6-3, 6-1 to reach the quarterfinals once again in Madrid. Nadal's quarterfinal encounter with ninth seed David Goffin was another good test for the Spaniard who played sublime tennis once more, defeating the Belgian, 7-6 (3), 6-2 to reach the semifinals for the fifth successive year.

The Spaniard is looking to equal Djokovic's haul of 30 Masters 1000 titles (Photo by Julian Finney / Getty Images)
The Spaniard is looking to equal Djokovic's haul of 30 Masters 1000 titles (Photo by Julian Finney / Getty Images)

Djokovic's route to the semifinals

The defending champion also received a bye in the first round, and he also had a tough second round match like Nadal. The former world number one endured a tough three-set battle with former top ten player Nicolas Almagro. Nevertheless, the defending champion recovered from a 3-0 deficit in the final set to defeat the Spaniard, 6-1, 4-6, 7-5.

The fire in Djokovic's belly is finally back, as he had to endure another tough battle with Feliciano Lopez but came through in straight sets, 6-4, 7-5 to reach the quarterfinals for the second successive year. Djokovic's straight-sets victory over Lopez was his first win in straight sets since defeating Kyle Edmund in Indian Wells. Unfortunately, 2014 finalist Kei Nishikori withdrew from their quarterfinal encounter due to a wrist injury,  handing Djokovic a walkover into the semifinals.

The Serb is looking to gain a huge victory over an in-form Nadal for the 27th time (Photo by Clive Rose / Getty Images)
The Serb is looking to gain a huge victory over an in-form Nadal for the 27th time (Photo by Clive Rose / Getty Images)

Their history

The two Career Grand Slam winners have met on 49 occasions with Djokovic leading their head-to-head 26-23, including a seven-match winning streak over his fellow former world number one. The Serb leads 14-10 in finals overall, 3-2 in ATP World Tour matches, 1-0 in their solitary ATP World Tour final meeting, 16-9 in Masters 1000 matches and 7-5 in Masters 1000 finals. However, Nadal has the edge in Grand Slam matches by leading 9-4 and 4-3 in Grand Slam singles finals. The Spaniard also leads 14-7 on clay courts, but Djokovic has an overwhelming 18-7 lead in hard court encounters and Nadal leads 2-1 on grass courts.

The Spaniard's first two victories over Djokovic was in the quarterfinals of the French Open in 2006 when he led two sets to love and Djokovic retired from the match at the end of that second set. Nadal also won their first Masters 1000 final meeting at Indian Wells in 2007 in straight sets. Djokovic's first victory over the fourth seed was in the quarterfinals of the Miami Open in 2007.

Nadal has defeated Djokovic in semifinals at the Mutua Madrid Open before in 2009. The Spaniard saved three match points and defeated his rival in four hours and two minutes. Other significant results in their meetings were Nadal's victory over Djokovic in the final of the US Open in 2010 in four sets to complete his Career Grand Slam and win his third successive third Slam. He became the second man after Andre Agassi to complete the Career Golden Slam as he won the Beijing Olympics in 2008.

Nadal's last victory over Djokovic was almost three years ago at the French Open in 2014, which happens to be Nadal's 14th and most recent Grand Slam victory (Photo by Matthew Stockman / Getty Images)
Nadal's last victory over Djokovic was almost three years ago at the French Open in 2014, which happens to be Nadal's 14th and most recent Grand Slam victory (Photo by Matthew Stockman / Getty Images)

The duo met in the final of Wimbledon in 2011, and Djokovic ended Nadal's title defence and reign as world number one and became the first Serbian male tennis player to win Wimbledon. Once again, they met in the US Open final and Djokovic gained his revenge from last year's defeat at Flushing Meadows by winning in four sets to claim his first US Open title. They would meet for a third consecutive Grand Slam final, and once again, the Serb would get the better of Nadal in a battle that lasted five hours and 53 minutes, thus Djokovic won his third title at the Australian Open. Djokovic was on course to complete his Career Grand Slam as the duo would meet for the fourth successive time at the French Open, however, Nadal would end Djokovic's remarkable run at winning four Slams in a row and claiming his seventh French Open title.

Djokovic ended Nadal's remarkable 39-match winning streak at the French Open in the quarterfinals with an easy 7-5, 6-3, 6-1 victory. He became the second man in history to defeat the 14-time Grand Slam champion at the French Open after two-time finalist Robin Soderling, achieved this feat in 2009. Djokovic was tipped to complete his Career Grand Slam by taking out his biggest obstacle but he lost to Stan Wawrinka in four set. Nonetheless, Djokovic finally clinched the French Open title a year later, defeating Andy Murray in the final.
 

Who reaches the final?

This semifinal encounter between the duo will be their 50th meeting between the two players who have 26 Grand Slam singles titles between them. Nadal's 2017 has been sublime since compatriot and former French Open champion Carlos Moya has joined his coaching team. The nine-time French Open winner looks extremely fit and motivated every time he steps out on the court. Nadal will be looking to lay down a marker ahead of the French Open with a victory over Djokovic, and firmly cement himself as the favourite. The four-time Mutua Madrid Open champion will need to serve well against Djokovic, who is arguably the best returner in the men's game. Nadal will have to take some risks and will have to trust his forehand and not hesitate to play the big points well. The Spaniard's forehand has been devastating this week, and Nadal's movement around the Spanish clay courts have been second to none.

Djokovic's victory over Nadal at Wimbledon in 2011 was the Serb's first Slam victory not on hard courts (Photo by Clive Brunskill / Getty Images)
Djokovic's victory over Nadal at Wimbledon in 2011 was the Serb's first Slam victory not on hard courts (Photo by Clive Brunskill / Getty Images)

The defending champion will also have to serve well against Nadal, and the duo will expect to play long rallies, which both players excel in but Djokovic is slightly fitter than Nadal. The Serb hasn't got a coaching team at the moment as he fired his team last week which included his long-term coach Marian Vajda. However, there are strong reports that Andre Agassi could take the reigns, which would be a very good partnership. The Serb always turns up for the big matches, and he will fancy his chances of defeating Nadal and retaining the title.

This will be the first semifinal scheduled at not before 4pm local time on the Manolo Santana court. Nadal will have the crowd firmly behind him, and the winner of this semifinal clash will face a first-time Masters 1000 finalist in Pablo Cuevas, eighth seed Dominic Thiem or lucky loser Borna Coric. Djokovic is slowly but surely getting back to his but Nadal's confidence has done him the world of good and should get over the line and compete in his first final in Madrid since 2015.

Prediction: Nadal in three sets.