Federer lobs to keep himself in a rally, Lajovic goes cross-court - and Federer's attempt at a return doesn't clear the net.

Deuce.

We've edged 10 minutes in this game, the longest of the match so far (if you don't count that Dart medical time out) and Karolina Pliskova is having to do some serious work.

The Czech does just enough to stave off that latest break point and hold serve.

Whoopsie.

Federer looks irk as he spears a backhand way out of bounds.

He's got another set point to play with, though.

Dusan Lajovic opens up his arm in a "what can I do" sort of way as he gets to the net, Federer nowhere in sight, and larrups a forehand long.

Oh! That's fine, fine work from Federer, running to his right and whipping a winner down the line, and he has two set points to his name.

Pliskova is furious, she pops a straightforward forehand into the tramlines and then the Czech goes long as the Dart goes on the offensive.

Break point for the Brit.

Oh! Dusan Lajovic does well to reach a Federer volley and the two have some quick forehand exchanges at the net, before Lajovic slices a ball out.

Fed bangs an ace down for good measure as he races to yet another hold. Fifteen minutes on the clock, and Federer is a game away from the first set.

Harriet Dart ekes out another break point.

Karolina Pliskova goes deep, catches the line and Dart can't drag it back over the net. The Czech works it for advantage, but a jumping, scuttling Dart scrambles back to deuce again.

And now another break point. Saved with a smash from Pliskova!

Nervy start to this deciding set.

And Marin Cilic gets the break to lead 4-3 in the third set.

The third seed looks in a mood to finish things off quickly against Yoshihito Nishioka.

And once again, Federer only needs one!

Lajovic is camped on the baseline and he misses an easy forehand. That's the fourth game in a row for Federer.

Boris Becker
Three-time Wimbledon champion on BBC TV

It looks like Federer has settled in nicely, putting a lot of pressure of the Lajovic serve.

A terrific rally from Dusan Lajovic, going down the line to wrongfoot Federer, before the Serb darts to the net and volleys over a winner.

You don't beat Federer much at teh net, though. He races to a 15-30 lead before he comes forward, an open court in front of him, to smash winner.. and misses.

Two break points for Fed.

Five aces in that last set for Harriet Dart to Karolina 'ace machine' Pliskova's one.

Not bad at all.

Can she take that momentum into this final set?

Double fault from Pliskova, and a superb backhand winner down the line follows as Dart fights back for deuce.

Over on Court two, last year's beaten finalist Marin Cilic looks to be on his way to the second round.

The Croat, the third seed, leads Japan's Yoshihito Nishioka, who is on his way back after an 18-month injury battle following a ruptured ACL.

Sam Smith
Former British number one at Wimbledon

That was fantastic composure from Harriet Dart to win that second set after such a long injury break. Her attitude has been top notch and there has been a transformation in her game from even a year ago. It was a very neat and tidy set from Harriet, who won a lot of points on her first serve.

Image source, Reuters

Roger Federer had a hit this week with Aidan McHugh, a British junior who is one of Andy Murray's mentors.

Which explains this comment...

An incredible story brewing over on Court 12. What a second set performance by Harriet Dart.

Back on Centre Court, it's business as usual. Federer serves and volleys his way to an easy 40-0 lead, before Lajovic floats his own attempt at a drop shot into the net.

Some punchy serves coming off the strings of Harriet Dart. She zips her way to 40-0 and three set points.

And takes it! Dart fist pumps in delight. She's levelled up against the former world number one.

And he only needs one!

Pushed out wide, Lajovic tries to whip a return cross-court and the ball ends up in the foot of the net.

First break to Federer.

These two did meet at Wimbledon last year - Federer went down a break early on, but the Swiss ultimately claimed a straight-set win.

Federer darts to the net, hurrying Lajovic, and out of nowhere, Federer has three break points...

Karolina Pliskova holds for the first time in this second set. She nearly took the strings out of Harriet Dart's racquet with that final serve...

But it's the British 21-year-old who finds herself serving for the set.