Grigor Dimitrov has taken charge of the third set with an early break of serve.

The Bulgarian stormed the first, before Stan Wawrinka fought back to win a tie-break in the second.

But it's the sixth seed who leads 3-0 in the third.

Right then.

Can Rus back up the break with a hold?

Three break points for Katie Swan!

She pops a return back into mid-court and Irina-Camelia Begu drags it into the tramlines.

She's two holds from the second round.

Mark: Why has Arantxa Rus won so little on the WTA? Got some game on her and a cracking forehand.

There is the break for Arantxa Rus!

It's not a good serve from Serena Williams and she slaps her resulting backhand into the net.

Now then!

A Serena forehand is blazed into the net, and it's break point to Rus.

Martina Navratilova
Nine-time Wimbledon singles champion at Wimbledon

I have never seen Serena this passive positionally on the court, giving up a lot of real estate on the net. It's got to be that she hasn't played enough matches.

Oh, what a lob!

It's actually a mis-hit from Arantxa Rus but she's nailed the ball right onto the baseline, and it's going to deuce.

Serena rests her head against her racquet in annoyance.

A terrific strike down the line gets Serena to 30-15 - and a man in the crowd takes a good catch off the ensuing shank from Rus - and then an approach pays off for the American.

Serena comes darting across to meet a ball that bounces on the baseline. Linesman calls out as Serena smashes a winner - and the umpire overrules the out call.

Replay the point!

Image source, Reuters

Well, Roger Federer began his quest for a record-extending ninth Wimbledon men's singles title with a routine win over Serbia's Dusan Lajovic, taking the first-round meeting 6-1 6-3 6-4.

Third seed Marin Cilic also reached the second round with a comfortable straight-set win over Japan's Yoshihito Nishioka.

But US Open champion Sloane Stephens became the biggest casualty on the opening day of the women's draw as she lost 6-1 6-3 to world number 55 Donna Vekic.

Second seed Caroline Wozniacki progressed with a 6-0 6-3 victory over Varvara Lepchenko, while British wildcard Harriet Dart pushed Karolina Pliskova close before losing 7-6 (7-2) 2-6 6-1.

There were also wins for Venus Williams and Madison Keys, while Sam Querrey and Daniil Medvedev progressed in the men's draw.

Katie Swan rattled through that opening set in just 29 minutes. She's won 95% of her first serve points so far today, complemented by some punchy baseline strokes, and is yet to give Irina-Camelia Begu a break point chance.

Swan holds again to keep it 3-2 on serve in the second set.

Over on court two, Gael Monfils has smashed a serve that has clocked 150 mph.

Commentators Nick Mullins and Mark Petchey were slightly dubious about the speed gun being correct but if it's verified then that's the joint 12th fastest serve ever recorded.

Serena makes a terrible challenge to a return that drifted well long.

40-0 to Arantxa Rus - before a slice return from Serena flummoxes her, and she sends her own slice into the bottom of the net.

Rus passes Serena easily, though, to clock a comfortable hold.

Stan Wawrinka fights back!

The Swiss takes the second set on a tie-break to level with sixth seed Grigor Dimitrov in a mouthwatering clash on Centre Court.

The order of play is fresh off the presses and British number one Johanna Konta will open proceedings on Court Two on Tuesday as she aims to emulate her amazing run last year.

She takes on Russia's Natalia Vikhlyantseva, who is ranked 106th in the world.

Meanwhile Kyle Edmund, the men's British number one, is first up on Court One against Alex Bolt of Australia.

Defending women's champion Garbine Muguruza plays first on Centre Court, as tradition dictates, with Rafael Nadal and Simona Halep following.

With England playing Colombia in the last 16 of the Fifa World Cup at 1900 BST, that match could potentially clash with Brit Heather Watson, who is fourth on Court 12.

Solid start to the second set from Katie Swan.

The 19-year-old was knocked out in the first round at Wimbledon last year, but could be set to go one better this time around after taking the opener against Irina-Camelia Begu.

It's 2-1 to the Brit on serve in the second.

Serena comes up to the net and this time the move does work, Rus on the run as she returns the volley and Serena smashes the winner over.

Advantage, Serena - and she holds as a Rus return floats long.

Saj Chowdhury
BBC Sport at Wimbledon

That didn’t take long.

An early break set the young Swanny on her way to the first set against Begu on Court 14.

It’s standing room only for many who have congregated.

Swan will be looking to end this fairly sharpish.

In a recent interview she revealed she watches Love Island...as does Andy Murray. You know Andy, you can watch the series on catch-up ;)

Image source, BBC Sport

That's an excellent time to find your first serve.

Rus can't return cleanly, and we're at deuce.

Serena finally comes forward, and she should really take the point, but Rus puts some extra fire on a return and Serena's volley doesn't clear the net.

Hello. Break point to Rus as a Serena backhand flies long.