OK, what they don't tell you about Philippe Chatrier is that the stairs from the dressing rooms to the court are as steep as Everest!

Zverev and Molcan look exhausted already as they ascend on to court.

I'd have needed to have a breather at halfway.

Arthur Rinderknech is the last French player standing in the singles, men's or women's, and he has the home crowd roaring with a break of serve in the opening game!

Taylor Fritz raced into a 40-0 lead but Rinderknech won the next four points.

He overhits a volley to let the first break point slip but comes back strong and makes no mistake with the second.

That's how you pump up a home crowd!

BBC Radio 5 Live

Don't miss a single point. We'll have radio commentary following all the drama on Philippe Chatrier from 19:30 BST.

If you're in the UK get listening by clicking the play icon at the top of this page.

As always, you can have your say on all of tonight's French Open action. Get involved by tweeting us using #bbctennis.

We'll also be giving you lucky people the occasional update from home favourite Arthur Rinderknech's match with ninth seed Taylor Fritz on Suzanne Lenglen.

Rinderknech has never reached the third round of a major, while American Fritz made it all the way to the last eight of Wimbledon last year.

Their match will get going very shortly.

Image source, Getty Images

The night session features a men's singles match for the fourth time in five days with former semi-finalist Alexander Zverev taking on Alex Molcan.

The night sessions, promoted as the highlight of the day at a major, have yet to feature a women's match.

The tournament was heavily criticised last year when only one of the 10 night session matches involved a female player, and director Amelie Mauresmo said in May that she could not promise there would be an equal share of men's and women's matches in the future.

Today's line-up has included Grand Slam champions Iga Swiatek and Elena Rybakina as well as crowd favourite Ons Jabeur, but Zverev will take on Molcan on the showcourt after Gael Monfils pulled out with a wrist problem.

Danish sixth seed Holger Rune's match against home favourite Monfils had initially been scheduled for the late session on Court Philippe Chatrier, but Monfils withdrew on Wednesday with injury, handing Rune a walkover.

Image source, Getty Images

Zverev, seeded 22nd, will face Slovakia's Alex Molcan as he bids for a first major singles title.

Molcan is ranked 86th in the world and has been frighftfully unlucky with the draw at recent French Opens.

Last year he was thrashed by Novak Djokovic in straight sets 6-2 6-3 7-6 (7-4) in the second round at Rolland Garros.

He's never faced Zverev in a competitive match. Will he pull off a shock tonight?

Image source, Getty Images

Germany's Alexander Zverev made a winning return to the tournament two days ago, a year after leaving his Roland Garros semi-final in a wheelchair with a serious ankle injury.

The 26-year-old retired in the second set of his semi-final against Rafael Nadal last year and was out for six months with torn ligaments.

Tonight he's back on Court Philippe Chatrier 12 months after his injury.

In the first round he beat South African Lloyd Harris 7-6 (8-6) 7-6 (7-0) 6-1.

"It's very, very nice to be back," he said in his on-court interview.

"I was obviously very disappointed with how that tournament finished for me [last year].

"That's why I appreciate it even more when I play in a full stadium and the crowd is behind me. It was just a lot of fun out there."

Righto, let's quickly switch our attention to Court Philippe Chatrier for tonight's night session where Alexander Zverev will shortly be taking on Alex Molcan.

Here's everything you need to know...

Coco Gauff, speaking on court after her win over Julia Grabher:

"It feels great. She's a tricky player, I played her on hard court earlier this year and she gets a lot of height and depth on her balls."

On playing singles and doubles [with Jessica Pegula]:

"I love the game and I honestly love playing with Jess, doing well on the singles and doubles court makes it fun for me.

"I'm not going to play doubles forever but I have the legs and the youth for it now so I'm going to enjoy it while it lasts."

Julia Grabher may be serving to stay in the French Open but she's not prepared to go down without a fight. A lovely little drop shot is followed by a forehand pinged into open court.

Though Gauff pulls a point back, she seals the hold to put the pressure back on the sixth seed to serve out the match.

After a fluke return from Julia Grabher surprises Coco Gauff by landing in, she levels on her serve with silky play at the net.

The American misjudges the flight of another Grabher strike, a forehand dropping flush on the line, but she's soon level as a Grabher backhand lands between the tramlines.

Gauff brings up game point with a powerful backhand giving her opponent no chance, and she gets the hold.

She needs just one more game on the board to reach the third round.

Is this where Coco Gauff takes control?

She wrongfoots Julia Grabher to go 15-30 up on the Austrian's serve, before Grabher sents a forehand into the net to gift the American double break point.

Gauff takes it on the first, responding to a Grabher serve with a forehand pinged into space.

Look at that. A hold!

Grabher goes 0-30 up but Gauff pegs her back, moving ahead to 40-30 before sending a serve down the middle that the Austrian can only deflect out.

A fist pump and a roar from Gauff. She needed that.

From 30-0 down, Coco Gauff brings herself back into the game, coming into the net to smash away a high return to level after a deep 18-shot rally.

Grabher pings down an ace for game point only to skew a return wide, but gets the advantage from deuce as she forces a sprinting Gauff into the error.

Grabher squanders her second chance too, a backhand slammed into the net, before Gauff unleashes a screamer of a backhand return into the corner for break back point.

She gets the break back as Grabher finds the net again.

Again...anyone going to hold? We've had seven breaks in a row now.

Coco Gauff casts a frustrated figure as she double faults again to put Julia Grabher up 0-30.

A forehand return clips the net cord and drops back on her side of the court to gift Grabher three break points of her own.

A stunning winner on the first earns Grabher the break. Anyone going to hold in this set?

But then it all falls apart.

Coco Gauff wins the first point of Julia Grabher's serve before back-to-back unforced errors hand Gauff triple break back point, with another gifting her the break back at the first opportunity.

A game of two halves.

Superb stuff from Coco Gauff early in the opening game of the second set. Beautiful footwork to go 30-15 up on serve, and a beautiful drop shot for 40-15.

But her first game point goes begging as she scoops a backhand high and wide, and then her second as she pings a forehand into the net.

Gauff double faults at deuce to hand Grabher the early chance of a break, which the Austrian takes with a forehand sent down the line.

A chance of a comeback for Julia Grabher quickly diminishes as a double fault plus two back-to-back errors give Coco Gauff triple break and set point.

Grabher saves the first but puts too much behind a backhand on the second to wrap up the set for Gauff.