World No.1 Jon Rahm's roller coaster year takes another wild turn on Thursday when he defends the US PGA's BMW Championship title on a course he hadn't seen before Tuesday.

The 26-year-old Spaniard won last year's FedEx Cup playoff event at Olympia Fields near Chicago, sinking a 66-foot putt on the first extra hole to defeat Dustin Johnson in a playoff.

This week, he tries for a repeat on a course new to the tour, Caves Valley in suburban Baltimore, Maryland.

"I know nothing about it. Absolute zero," Rahm said on Tuesday. "I really know nothing. For everybody I've asked that has played here, it's a great golf course."

Rahm's season has included his first major victory at the US Open in June at Torrey Pines and the arrival of his first child, wife Kelley giving birth to son Kepa just before the Masters in April.

But in June, Rahm had a six-stroke lead after the third round as defending champion at the Memorial tournament when he was forced to withdraw after testing positive for COVID-19.

In July, Rahm was forced to miss the Tokyo Olympics after again testing positive for COVID-19. And last week, Rahm led much of the way at the Northern Trust only for a hurricane to postpone the final round to Monday, when he settled for third.

"I'm looking for just a normal tournament week at this point, just one week where it's just uneventful, we don't have hurricanes, COVID or anything like that," Rahm said.

"Luckily I can say there have been a lot more positives than negatives. There were some moments that could have taken me down that, if anything, lifted me up and pushed me towards greater things.

"The overall condition that the world is in with COVID, I can be very glad that nobody in my direct family has had any problems and that hasn't been a stress, when I know a lot of people have been suffering. It could have been a lot worse.

"It has been a great year. Still not over. A lot more things to play for, and hopefully I can keep making it better."

Only a three-hour drive from Liberty National, Rahm made a quick exit to try and get two practice rounds at Caves Valley, giving little thought to missing out on a win in the first PGA playoff event.

"Simply because we had to get back, pack, sleep, travel, I haven't really had time to think about it," Rahm said.

"There are a lot more positives to take out of it than negatives. There are a lot of good things I did last week and hopefully I can keep those going on."

The top 70 players in season points advanced to the BMW with only the top 30 after ­Sunday's final-round qualifying for next week's Tour Championship at East Lake in Atlanta.

Rahm is safely in second place on points but would like to be in top position for next week's title fight.

"It's the week before East Lake, so I think we're all trying to get into form right before our very last big event," Rahm said.

"It's definitely something I have in mind, and I can't help to think that I hope I make this my first defense on the PGA Tour."