Deckard: This fight has a Ruiz jnr win written all over it.

Dr. Mark S. Elliott: Really looking forward to Joshua/Ruiz II. Difficult one to call, but I'm siding with AJ on the grounds he's learned from the first fight, and that second chances should be grabbed with both hands.They don't come for everyone, so got to take it.

Steven Garwood: Think Joshua is done if he loses! Ruiz knockout in the 6th.

Richie Woodhall
Former world champion at Diriyah Arena for BBC Radio 5 Live

He looks very serious. His eyes are fixed.

Anthony Joshua is kitted up and ready to go in his changing room. Pure focus in the eyes of the challenger. It's almost time for the ring walks...

Andrew Priestly: Career on the line for Anthony Joshua tonight. Who would have thought that could be the case 12 months ago?

Hall of fame promoter Bob Arum: "I like Ruiz to win again. He is really an under-rated guy. His low centre of gravity works well against a big heavyweight and his hand speed is phenomenal. His style plays to Joshua's weaknesses."

Former world heavyweight champion Hasim Rahman: "I am leaning at the moment to Ruiz by knockout. I just think Joshua has lost weight. I feel he may have lost muscle and that can be detrimental."

Let us know your prediction using #bbcboxing

A second Andy Ruiz Jr win would spark immediate talk of him facing WBC champion Deontay Wilder, who is due to meet Tyson Fury for a second time in February.

Wilder and Ruiz share the same advisor, so boxing could, in theory, be within touching distance of a first ever bout for all four heavyweight belts.

There is no rematch option in the contract this time, so were Anthony Joshua to win, he too could look to Fury or Wilder to set up a captivating 2020 in the glamour division.

On the other hand, a second loss would limit Joshua's options in the short term and undoubtedly produce calls for him to hang up his gloves.

Even in defeat, that would seem a harsh verdict on a man who has achieved so much in so little time.

Image source, Getty Images

Richie Woodhall
Former world champion at Diriyah Arena for BBC Radio 5 Live

It is a strange situation because there is usually a lot of pressure on a champion when he is defending his title.

But this is similar to the first fight when Ruiz had no pressure on him, although there is a little bit more on him this time. He still knows everyone thinks he is going to get beaten again so he thinks he is the underdog.

Andy Ruiz has met the president of Mexico, been interviewed by US talk show host Jimmy Kimmel, he has thrown out the first pitch at a Los Angeles Dodgers game and he has been paraded on the back of a convertible Rolls Royce through the city he grew up in.

The man ridiculed for his rotund physique has even started modelling for a menswear brand.

There have been new gold and diamond chains, and in the words of the champion himself, "fun things I always wanted".

He told Radio 5 Live's Mike Costello and Steve Bunce he "has not stopped smiling" since he beat Anthony Joshua in June.

Luke Reddy
BBC Sport in Riyadh

Image source, .

Anyone fancy a nice Christmas gift?

You can get this out of the Welsh valleys if you like as artist Patrick Killian has grafted on it, brought it to Saudi Arabia and got it signed by Anthony Joshua and Andy Ruiz.

It’s quite the stocking filler...

Boo Boo Bear: Richie Woodhall said he didn't think Joshua was fit in his last fight v Ruiz. At the time I thought he'd underestimated the Mexican, expected an easy win, & was caught out. Thoughts?

James Agar: I'm expecting a Joshua 2nd round knockout.

Luke Reddy
BBC Sport in Riyadh

The entire arena just stood to put ponchos on.

I spoke to the guy who told the organisers they should hand ponchos out at the event. He told me he was laughed out of town when he brought that up at a meeting.

Give that man a pay rise.

Ponchos back on, it's raining again in the desert...

Image source, Getty Images

Image source, Instagram

Perception of Andy Ruiz Jr has changed since the first fight. His weight is slightly heavier yet he has moved from being regarded as a chubby walkover to a fast-moving threat.

"It felt bad as he's my son, that's his weight," says Ruiz Sr.

"I told people I would bet money on him winning [the first fight] in the seventh round. People were asking why I had such faith. They wouldn't take the bet so I went to the casinos and bet money and won.

"I made a lot of money. I knew he would win.

"His mother and me can see that he is doing better. As a dad I feel so proud that he is doing the things that he wants. Not a lot of boxers make it. It's like winning the lottery."

Anthony Joshua tells Mike Costello and Steve Bunce that he "had to reinvent" himself after losing to Andy Ruiz Jr and that tonight's rematch in Saudi Arabia is his "time to right his wrongs".

Luke Reddy
BBC Sport in Riyadh

Image source, .

I’m not too sure the Saudi crowd fully get just how important this is for Joshua and Ruiz. They of course know it’s a big event but as far as awareness of the magnitude of the contest, who knows?

What I do know is those who were at Madison Square Garden on 1 June are pretty silent right now. There’s a real tense feeling.

Earlier, on my way here I saw some of Joshua’s team. They too spoke of some real nerves. His bodyguard was smoking and downing an energy drink. I think we might all need to call on something to get us through a sapping night of drama.

Now then, it's almost time for the big one...

Get yourself in the mood by watching again the key moments from Anthony Joshua's shock defeat at Madison Square Garden in June.

"I would love to do it again," says Michael Hunter.

Alexander Povetkin adds that he "respects Michael very much", so looks like we'll be getting a rematch...

Luke Reddy
BBC Sport in Riyadh

Image source, .

The two photos are six months apart.

One is on a New York rooftop, one is on a Riyadh balcony. Andy Ruiz is the same man in both but at the same time he kind of isn’t.

In New York in the top image, he was an unknown, pressure-free guy who had turned up to have a swing and probably get knocked out.

In Riyadh he has a country behind him, money, pressure and expectation. The stakes feel so much higher for him this time thanks to a shock we will never forget.