GB's Dan Evans loses to Federer 4-6 2-6 2-6 on Centre
Play will be held on Sunday to clear backlog
Djokovic 6-7 1-6 Querrey when rain stopped play
GB's Tara Moore loses 1-6 6-2 3-6 to Kuznetsova
Serena Williams beats Christina McHale 6-7 6-2 6-4
Jonathan Jurejko
BBC Sport at Wimbledon
Image source, BBC SportHooray! Here's something we've not seen for a while...sunshine. The covers might still be on Court 18, but the fans sat in the stand - and those over yonder on Henman Hill - are starting to peel off their protective layers. Not quite time to dig out the sunglasses though.
Someone's keeping busy during the rain delays...
Del Potro 3-6 6-3 1-1 Wawrinka
Mark Petchey
BBC Sport
"It was a stunning shot down the line from Wawrinka to win that game."
John McEnroe adds: "It looked like Stan was heading in the wrong direction, but he brushed it all off and showed why he was won two Slams."
*Del Potro 3-6 6-3 1-1 Wawrinka
We're having a spell of you break, I break on Centre Court.
Fourth seed Stan Wawrinka lets out a roar towards his coaches as he immediately snatches a game back off Juan Martin del Potro.
After a dodgy second set, has the Swiss got his head and game straight again?
Image source, Getty ImagesMark Petchey
BBC Sport
"While it was raining, I kept myself out of mischief by working out how many times Roger Federer has played on Centre Court. It's 71, if you were wondering."
#bbctennis
Tom Killalea: Is it just me or does Stan looked to have lost it a bit mentally? He's not hitting through the ball with such confidence now.
Image source, APDel Potro 3-6 6-3 Wawrinka
Image source, .Del Potro 3-6 6-3 Wawrinka
Wawrinka serves a double fault
This was a crucial moment in the match. Stan Wawrinka double faults...and goes on to lose the second set.
Del Potro 3-6 6-3 Wawrinka
A trademark huge serve from Juan Martin del Potro evades Stan Wawrinka and the Argentine takes the second set.
He nips off court for a comfort break, while Wawrinka ponders his next move.
*Del Potro 3-6 5-3 Wawrinka
Stan Wawrinka goes to sit down because he thinks his backhand has gone out, and therefore the break and set has gone to Juan Martin del Potro.
But we go to Hawk-Eye...and it's hit the chalk! Back up on your feet, young Stan.
The Swiss fourth seed goes on to take the game to make Del Potro serve for the set.
Image source, Getty ImagesThe Wimbledon announcer has just confirmed that they hope to get play under way on the outside courts at 14:45 BST.
There's a ripple of applause on Centre Court as the sun comes beaming through the transparent roof.
Has the rain finally cleared for day five? Here's hoping.
Del Potro 3-6 5-2 Wawrinka*
Mark Petchey
BBC Sport
"The tennis has entered the best stage of the match here, with both men playing at the best level they can."
Del Potro 3-6 5-2 Wawrinka*
As you may have heard on the BBC commentary, Juan Martin del Potro has been dogged by injury in recent years.
The former US Open champion has battled his way back from three wrist operations that almost called time on his career.
But the 27-year-old Argentine came through his first Grand Slam match in 894 days here in round one, with a 6-1 7-5 6-0 win over France's Stephane Robert, and he looks in good form against Stan Wawrinka here on Centre.
The big man holds his serve to move 5-2 clear in the second set.
Image source, Getty ImagesSo now all of the outside courts are off again.
Venus Williams and Daria Kasatkina did try and play on Court One. They got through four games before it was deemed too wet to continue.
Fingers crossed the skies clear soon so we can see an afternoon of tennis goodness.
Image source, AP*V.Williams 3-1 Kasatkina
Lindsay Davenport
Former Wimbledon champion on BBC TV
They are the only two players who have been subjected to play in this steady mist and drizzle, that doesn't seem right .
*Del Potro 3-6 4-1 Wawrinka
John McEnroe
Three-time Wimbledon singles champions on BBC TV
You don't want to wake a bear that has been in hibernation for a while.
Del Potro 3-6 4-1 Wawrinka
Mark Petchey
BBC Sport
What a let down that was from Wawrinka.
Pressure seemingly getting to him there.
Del Potro 3-6 4-1 Wawrinka
An early break point for Juan Martin del Potro early on in the second set. Can the Argentine capitalise this time?
Well, yes, as it's handed to him on a plate after a Stan Wawrinka double fault.
And then Del Potro holds on his own serve to move 4-1 up.
The momentum is swinging in this match on Centre.
Del Potro wins the point after an exciting rally
Del Potro may have lost that first set but he won the point of the match so far, which you can see above.
#bbctennis
Daniel Woods: Both players know how to hit those balls hard, but my goodness Del Potro is something else!
Goran: Rain delays might actually be good for Venus after playing two matches yesterday.