The 60-year-old coached Messi and Busquets at Barcelona in 2013-14 before managing Argentina from 2014-16.
The move is also a big win for MLS, which welcomed Messi while adding that work remained to finalise the details of the formal agreement.
Max Verstappen beats Sergio Perez to win his 3rd race of the season.
Medvedev improved to 6-0 lifetime against Sinner. He is 24-1 since January's Australian Open.
By winning her 30th career title, the former world No. 2 Kvitova will now re-enter the top 10 for the first time since September, 2021.
Ekaterina Alexandrova advanced to the last eight.
The US currently bars unvaccinated foreigners from entry into the country, a policy that is expected to be lifted when the government ends its COVID-19 emergency declarations on May 11.
The victory was the Dutch driver's third of the season, and second in a row, and he made it happen with a crucial overtake around the outside on Sainz at the start to seize second place before blasting past Leclerc on the ninth of the 57 laps.
The 18-year-old Alcaraz earned his first ATP Masters 1000 crown and is the first Spanish man to triumph in Miami after eight previous final appearances by his compatriots, including five by Rafael Nadal.
Swiatek also became the first woman to win the opening three WTA 1000 tournaments in a season.