FIDE Candidates 2020 - MVL replaces Radjabov!
I just saw the news on the FIDE website that Teimour Radjabov (the winner of the 2019 FIDE World Cup) withdrew from the 2020 FIDE Candidates, and will be replaced by Maxime Vachier-Lagrave!

I saw someone claim on Twitter that this is due to the coronavirus outbreak, but I would prefer not to speculate. Instead, let's look back on the journey of these two players last year, in the qualification process for the 2020 Candidates.
As I noted above, Radjabov qualified by making the finals of (and then, winning) the 2019 FIDE World Cup. Ironically, he knocked out MVL in the second game of their semi-final match to advance to the final and secure his place in the 2020 World Cup. Here is that game:
We already saw that MVL narrowly missed out on qualifying for the Candidates via. the FIDE World Cup (where he finished in 3rd place) and, initially, by highest average rating (coming 2nd on this measure among the eligible players, after Anish Giri).
The first of these events that MVL participated in was the Riga FIDE Grand Prix. He put in a phenomenal performance, consecutively defeating three elite Grandmasters in the classical phase of the match to gain three 'bonus points' in the Grand Prix standings. Here are those key wins.
First, in Round 1 against David Navara, where he made the Caro-Kann look like an inferior opening:
Second, a very nice win against Topalov, after Topalov's piece sacrifice was not entirely successful:
Then, MVL knocked out Grischuk (who would go on to win the FIDE Grand Prix with 20 points) by switching to a Benko after Grischuk's unusual 3.h4:
In that Armageddon game, it was Mamedyarov's nerves that proved stronger:
In his 2nd FIDE Grand Prix tournament, in Hamburg, MVL again started extremely well, winning 1.5-0.5 against Wei Yi and (again) Topalov. However, in Round 3, he was knocked out by Grischuk, who played a very strong technical game to convert an advantage:
So, it all came down to the final FIDE Grand Prix event, in Jerusalem (December 2019). The FIDE Candidates qualification essentially came down to the Round 3 semi-final match between Ian Nepomniachtchi and Maxime Vachier Lagrave. Both these players are Grunfeld specialists, and both games indeed were in this opening.
The key game was the first one, where Nepomniachtchi surprised MVL in the opening to get an advantage and ultimately the key win: