It is easy to get lost in the what-ifs.

British Athletics' selection policy for Tokyo Olympics

stretches to 18 pages, taking in two qualification periods, two sets of performance standards, selection summits, World Athletics invites, appeals, and more sub-clauses than an undergraduate essay.

But, if they perform well enough at this weekend's British Championships, Britain's best athletes can finally shred the small print and pick up their ticket to Tokyo.

Here, former world champion and three-time Olympian Steve Cram picks out the events to look out for.
Men's 10,000m (Friday, 21:35 BST)

This is essentially a time trial for two-time defending Olympic champion Mo Farah.

Farah finished second, behind Marc Scott, but more than 22 seconds off the automatic qualifying standard of 27 minutes and 28 seconds in the 10,000m British trial in Birmingham on 5 June.

It's certainly possible that he makes up that difference to book his place in Tokyo on Friday.

That run in early June was his first 10,000m on the track since 2017.

He had an issue with his ankle and, from what I understand, that has been improving. He has been out training at altitude in Font Romeu in France. Farah wouldn't be coming if he didn't think he had a good shot at it.

He has his Belgian training partner Bashir Abdi, who ran 27:24 earlier this month, to help pace him.

Women's 800m (final, Sunday, 14:50 BST)

This is going to be a super race.

Just this year, Jemma Reekie, Laura Muir, Alexandra Bell, Keely Hodgkinson and Adelle Tracey have all gone under the Olympic qualifying standard.

The first question will be whether Muir does both events.

The 1500m is her main event, but she is very dominant in that. Could she take on the 800m as well, with the additional heats that entails in a more evenly contested distance? It would be a very busy weekend.

But it is going to be hard for the selectors to include her in the 800m without her running given the strength of the rest of the field.

Reekie is probably the standout, but don't discount Ellie Baker - who has missed the qualifying time by a gnat's whisker several times this year - from getting in the top two.

Even the heats will be interesting. You have to win to guarantee your place - if you get in a slow tactical race and miss out, you might not event reach the final.
Men's 800m (final, Sunday 15:00 BST)

It is almost impossible to look at this in isolation. This is the strongest men's 800m for a long, long time. But it is indicative of the strength of middle distance running as a whole. You could say the same for the 1500m.

It is almost like the old days in the 1980s when Seb Coe, Steve Ovett and myself would think about doubling up. It will be really interesting to see who lines up where and what transpires.

Elliot Giles has the qualifying time for both, while Josh Kerr and Jake Wightman could also be considered for both.

British champion Daniel Rowden is a little inexperienced but fast-improving. Jamie Webb and Kyle Langford are right in the mix.

It is a shame that 19-year-old Max Burgin has pulled out with injury, but 20-year-old European junior champion Oliver Dustin, third fastest in the world this year, is a real talent.

It might well be a slow, tactical race, which might not suit those at those with the fastest times. It is all very intriguing, from Friday's 1500m heats onwards.
Women's long jump (final, Sunday 13:00 BST)

It looks a really tasty competition.

Jazmin Sawyers is coming in off the back of a huge 6.90m jump in California earlier this month.

She is one of a number of British athletes who have based themselves in the USA in search of competition this season. That is where the events have been, whereas it was more challenging to know what opportunities there were over here with the Covid situation.

Lorraine Ugen is the best of British this year with 6.94m, but Shara Proctor and Abigail Irozuru have both jumped in excess of the 6.82m qualifying standard in the required time period.

All of them have that big jump in them, but it will be about bringing it to Manchester and then beyond.

There is proper world-class depth there. If you start jumping 6.90m regularly, you are not going to be far away on the international stage.
Men's 100m (final, Saturday, 18:25 BST)

Normally we have four or five guys on the top of their game as the trials come around. I'm not sure we can say that this time around. It all looks a little more uncertain.

CJ Ujah has had a good season and looks to be the standout of the fit, healthy and regularly racing.

Zharnel Hughes, Reece Prescod and Adam Gemili also have the qualifying time, but from back in 2019.

Gemili didn't look great in early season, but never write him off. He has a great habit of getting right when he needs to.

Just look at 2019, where he was within 0.05secs of a medal in Doha.

The 100m may be wide open at the Olympics. There will be no Christian Coleman or Noah Lyles to really stamp their authority on it. For the British guys who do make it, there is an opportunity.
Women's 400m hurdles (final, Saturday 15:00 BST)

The quality has really kicked on in this event.

Meghan Beesley was top of the British timing charts in 2019, running low 55-second times. This year, that sort of time might only be good enough for fourth.

Jessie Knight has run 54.74 seconds and Jessica Turner has clocked 54.77, while Lina Nielsen, at the age of 25, has suddenly really got to grips with the event. She has taken nearly a second and a half off her personal best this season.

It is going to be a great contest between those four. The competition might take their times down to low 54 seconds or below this weekend.

Steve Cram was speaking to BBC Sport's Mike Henson.