Maria Sharapova is gnawing away at Eugenie Bouchard's game, playing the percentages, going for the winners only when she has a decent margin for error.

It pays off as well, two break points at 15-40 via a couple of Canadian errors, and Sharapova levels the set with a crisp forehand down the line beyond Bouchard's flailing racquet.

Image source, AP

Eugenie Bouchard is attempting to boss and bully Maria Sharapova and almost steals the Russian's serve along with her lunch money. A roundhouse of a backhand forces the Russian too far wide to get anything back within the lines.

Break point Bouchard. But there is the first hint of Sharapova's titanium nerves. She takes an age over her second serve at 30-40, perhaps waiting for a breeze to die down, but grinds out the subsequent rally to save herself.

Maria Sharapova is skipping and stalling at the back of the court, back to her opponent, as she dictates the pace of the game.

A yanked Eugenie Bouchard forehand give her a break point at 30-40. Saved in style - serve down the middle, forehand out wide, volley bulleted away.

A second break point for Sharapova from deuce is shooed away by a big Bouchard tee-off.

The Canadian is still swinging loose and limber, even under the pressure of break point.

Bouchard tightens a little, duffing a forehand with court open and unguarded, but is over the line at the next opportunity.

Mighty impressive, but Sharapova gets better as the situation gets sticker.

Annabel Croft
Former British number one on BBC Radio 5 live sports extra

"This is absolutely incredible from Bouchard. There is a real intensity of what she puts out on the court. There is a real aggressive mindset which takes your breath away. She likes to take the bull by the horns and gets into the net which is rare in the women's game and she is great at volleying."

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Image source, Reuters

Maria Sharapova steadies the ship with a hold to 15, but Eugenie Bouchard is creeping in to get after the Russian's second serve and snarling with aggressive groundstrokes.

She is as good as her pre-match words, showing no deference to one of the women's game's queen bees.

The young pretender is doing a fine impression of a four-time Grand Slam winner.

Eugenie Bouchard rips a meaty forehand down the line and is onto 40-0 as Maria Sharapova nets out wide.

Sharapova reminds the Canadian of her quality with a whipped pass, but is just groping at thin air as another rifle crack of a forehand puts the game to bed.

Maria Sharapova has lost the first set in each of her last two matches against Sam Stosur and Garbine Muguruza and she has made a sluggish start here.

Eugenie Bouchard is making hay while the world number eight fails to shine. Handed two break points at 15-40, she steps in and wallops away a fierce forehand winner to move a break ahead.

Annabel Croft
Former British number one on BBC Radio 5 live sports extra

"To get rid of nerves you need to run so for Eugenie Bouchard to have some good long rallies will certainly help. It's all very intense out there, you can really feel the tension between the two players."

You can listen to full coverage on BBC Radio 5 live sports extra

Maria Sharapova gives Eugenie Bouchard a helping hand up onto the scoreboard.

The Russian's groundstrokes are not trained as keenly as they might be on the whitewash and she clumps wide on a backhand at 30-30 before netting on the next point.

If Bouchard had any nerves coming into this, that will have helped settle them.

The two of them are both decked out in mixes of pink and orange, but there is nothing delicate about the opening exchanges.

Maria Sharapova slugs away three big serves as her opening salvo and Eugenie Bouchard is yet to pick it. A couple of returns long and, although she nibbles a point off the older woman at 40-0 down, that is all she is getting.

Maria Sharapova to get us going...

Piers Newbery
BBC Sport at Roland Garros

"The sun is finally shining on Chatrier and the stands are filling up at a leisurely, lunchtime pace. It will be interesting to see who the crowd are rooting for in this first semi-final, the young pretender or the former champion. Titles do not guarantee affection at Roland Garros but it's Sharapova who marginally edges the welcome cheer. Although neither woman will care a jot."

You know the drill. Text on 81111, tweet to #bbctennis, external and post on the BBC Sport Facebook, external page.

Thoughts, predictions and witticisms all welcome.

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Great Britain Fed Cup captain and mother to Andy and Jamie, Judy Murray will be part of the commentary team.

Earlier in the week, she compared Sharapova to a tea-bag, because "when you put her in hot water you find out how strong she is". The Russian was completely foxed by the simile when it was put to her.

"We're not friends, so there is that," said Bouchard.

"We're in the semis of a Grand Slam, so I'm going to respect her but not put her too high on a pedestal and really just battle.

"I was never here from day one to make friendships. This is a battlefield for me, and I want to win."

They are just a few moments away from appearing on Court Philippe Chatrier in the semi-finals of the French Open.

So, did Eugenie take up tennis because of Maria?

Did she swap clothing sponsors to be closer to the Russian?

While Bouchard admits to admiring Sharapova and her "cute dresses" as she was growing up, she insists she has left that behind.

Image source, Getty Images

It is was the first, but far from the last, time the pair posed together for the cameras.

Eugenie Bouchard has soared through the rankings, rising from 144 to 32nd in the world over the course of 2013, justifying the hype and hopes of marketing men who proclaimed her as 'tennis's next big thing'.

She was paraded alongside Sharapova as the face of the clothing sponsor the pair share,, external as well as appearing on court in two Tour defeats against the Russian.

Image source, @geniebouchard

Eugenie Bouchard and Maria Sharapova go back. Way back.

Back in March 2002, the Bouchards had travelled on a spring holiday from their native Canada down to Miami where they took in a bit of a tennis tournament, then known as the Nasdaq 100 Open, now the Sony Open.

Dad Mike spotted a rangy 15-year-old Russian making her way to the locker rooms and recognised her as Maria Sharapova, the winner of the tournament's junior side-show.

Mike Bouchard ushered his awed eight-year-old Eugenie forward and captured a snap of her alongside Sharapova, who was still two years from her breakthrough Wimbledon win.