© Realis/Rolex Monte-Carlo Masters

Fabio Fognini made 19 of 20 forehand returns in his straight-sets win over 11-time champion Rafael Nadal at the Rolex Monte-Carlo Masters on Saturday.

Analysis: Why Fognini Beat Nadal

Italian will meet Lajovic in the Rolex Monte-Carlo Masters final

The forehand broke.

Fabio Fognini stunned Rafael Nadal 6-4, 6-2 in the semi-finals of the Rolex Monte-Carlo Masters on Saturday with Nadal's forehand starting strong but misfiring the further the match progressed.

Nadal was broken in his first service game, then broke back twice in a row to lead 3-1 in the opening set. His forehand was behaving perfectly well in the first four games, as he made an impressive 46 of 47 forehand groundstrokes and returns, including one winner.

And then it started cracking into the beaten red earth. Nadal lost 10 of the next 11 games to trail 6-4, 5-0, with the Spaniard committing at least one forehand error per game, and sometimes four. Rarely have we seen forehand errors flow as freely from Nadal's racquet, as he described his performance as "one of the worst matches on clay in 14 years".

Nadal put 46 forehands in the court in the first four games, but only put 89 forehands in play in the next 14 games to the end of the match.The stark contrast can also be seen in the error column, as he had just one forehand error in four games, then 26 forehand errors in the next 14 games.

Overall, Nadal committed 27 forehand errors while hitting just five winners.

Nadal's Forehand: Winners & Errors
Forehand Return = 0 winners / 3 errors
Serve +1 Forehand = 1 winner / 5 errors
Return +1 Forehand = 0 winners / 3 errors
Rally Forehands = 4 winners / 16 errors
Total = 5 winners / 27 errors

What was shocking to see was how little control Nadal had over his forehand in the big moments. When serving at 4-4 in the opening set, Nadal hit seven forehands in the game, with four of them being errors. He lost his serve to love.

Fognini's forehand was solid throughout the match, particularly when returning serve. He hit 19 forehand returns for the match, missing just one of them.

Fognini's Forehand: Winners & Errors
Forehand Return = 0 winners / 1 error
Serve +1 Forehand = 3 winners / 4 errors
Return +1 Forehand = 2 winners / 2 errors
Rally Forehands = 4 winners / 10 errors
Total = 9 winners / 17 errors

Fognini won several small battles around the baseline, which all helped add up to his impressive victory. Fognini's average groundstroke speed for the match was 123km/h, which was faster than Nadal at 118km/h. Overall, Fognini played more down the line than Nadal (43 per cent to 32 per cent) from the baseline, identifying another area where he felt more control.

Court position was also a telling indicator of how well Fognini owned the baseline exchanges. The Italian only hit 22 per cent of shots from at least two metres behind the baseline, while Nadal hit 42 per cent of all shots after the serve and return from back deep behind the baseline. The Spaniard was trying to buy more time and not have his shots rushed, but it in turn opened up angles for Fognini to attack. Nadal only played 34 per cent of his shots from that deep in the court in his quarter-final victory over Guido Pella.

Nadal will now play in the Barcelona Open Banc Sabadell where he is the top seed. Fognini has one more match in Monte-Carlo - the final on Sunday against Dusan Lajovic.

- Data assistance courtesy Hawkeye and ATP Media