After a year’s worth of two-a-day practices, distance freestyle sets, grueling holiday training sessions, early mornings spent slogging up and down the pool, finally, at long last, it’s come down to the biggest and most important championship swim meet of the season for USA Swimming, the Pan Pacific Championships, held in Tokyo, Japan. Follow the action on the Olympic Channel each morning.

Importantly, this huge international competition also allows the U.S. team to get a taste of Tokyo — site of the 2020 Olympics. Though the Pan Pacific Championships are a celebration of competition in itself, this week can also serve as a dress rehearsal for the Olympics. Athletes competing will get an opportunity to travel halfway around the world, swim in a much different time zone, experience a different culture, and imagine what it will be like two years from this summer.

But that’s far into the future. Right now, the focus is on these Pan Pacs, and competing against top international talent. Swimmers qualified at the Phillips 66 Nationals earlier this summer; there were a few surprises and several swimmers who made a few upsets, and there were several recognizable names who qualified. Some of those swimmers have been looking towards these Pan Pacs to finally taper down. So, expect some fast racing. Expect down-to-the-wire finishes. Expect a world record or two to go down this week. And expect the United States to bring it.

As always, here are your 5 Storylines to Watch…

1. Can 19-year-old Michael Andrew better his Phillips 66 Nationals performances?

At the Phillips 66 Nationals in Irvine, one of the most impressive performances was by a swimmer who has, arguably, had the spotlight on him since he was 10-years-old. Michael Andrew, a swimmer who turned professional in his early teenage years, took quite a few top podium spots at last month’s Nationals. His most impressive races were the 50 freestyle and the 100 breaststroke. In the splash and dash free, he beat out veteran swimmers Nathan Adrian and Caeleb Dressel. In the 100 breast, he swam a blistering :59.3, proving that he belongs in the 100 meter distances as well. It should be a fun week to watch Andrew and see if he can better those performances under the international spotlight.

2. Kathleen Baker and the women’s 100-meter backstroke.

Baker was the talk of the town last month with a world record in the 100-meter backstroke. Baker nearly became the first-ever woman under :58 seconds. Could she break through that time barrier at this week’s Pan Pacs? She should have a few opportunities to do so, including the medley relay. She’ll have stellar international competition to push her. It would be quite a feat to break into the :57-second territory, but Baker is only one one-hundredth of a second away. She could do it this week.

3. Could veteran Matt Grevers take the Pan Pacs title?

Like a fine wine, Matt Grevers gets better with age. The 33-year-old Olympic gold medalist qualified for yet another international roster, scoring second place at last month’s Phillips 66 Nationals. Grevers swam a very quick :52.55, barely missing first place by less than a tenth of a second. Could Grevers take the Pan Pacs crown? This veteran knows how to show up for the big races, and with his 6’8” frame, expect him to be in the mix under the flags. It’s a race that could come down to the finish.

4. Simone Manuel, one of the USA’s greatest sprinters…

Manuel had another typical great week of racing at last month’s Nationals. Expect Manuel to eye a few Pan Pacs titles in the sprint freestyles this week. The big question for Manuel is, could she possibly claim a world record? Sarah Sjostrom’s world records are lightning fast, but Manuel isn’t far behind. Manuel’s got every ingredient it takes. I’m excited to see her race this week and see if she can catch or surpass Sjostrom’s records.

5. Of course, the big storyline of the meet will be Katie Ledecky.

Ledecky was basically a shoe-in to qualify for this week’s meet, so no world records were broken in Irvine. Expect that Ledecky will be fully rested and ready for Tokyo. We may never have another swimmer as dominant as Ledecky, so swim fans out there, be sure to watch along. We’re witnessing history in the making with every swim, every stroke. Even if Ledecky doesn’t break her own world records, her swims will be a story line in themselves.