Marc Marquez fastest during a wet opening practice for the 2021 Americas MotoGP at COTA.

Looking to restore his COTA dominance after falling from the lead in the most recent 2019 race, Marquez was fast from the start of the session before Jack Miller took over at the top with 25mins to go.

The Australian remained in charge, as the track began to dry under blue skies, until Marquez jumped 0.7s clear of Miller with five minutes remaining. The Ducati rider then trimmed Marquez's advantage to 0.167s.

Johann Zarco made a promising return from arm pump surgery by pipping Miguel Oliveira for third on his final lap, the KTM rider nonetheless enjoying one of his best sessions since his post-summer break slump.

Pol Espargaro made it two Repsol Hondas in the top four, with LCR Honda's Alex Marquez completing the top six. Team-mate Takaaki Nakagami was the only faller.

The Yamahas all continued to struggle in the wet, with world championship leader Fabio Quartararo left down in 15th place. Title rival Francesco Bagnaia was eighth.

It remains to be seen if the fine weather will continue and allow slick tyres this afternoon, or if more rain - a threat for most of the weekend - will arrive.

Marquez has a perfect pole record at the Texan track and has won six of the seven MotoGP races, falling while leading in 2019.

Suzuki's reigning champion Joan Mir has a Kevin Schwantz-style helmet and racing number this weekend.

MotoGP is returning to COTA for the first time since the 2019 event, after which further resurfacing work was carried out on around 40% of the track (Turns 1-2, 9-10, 16-19, plus the back straight) to alleviate bumps.

As a result of the resurfacing and change of date from April, Michelin is providing a fourth rear tyre option (two hard compounds).

COTA has the most corners (20) in MotoGP, including the slowest of the season at just 50km/h (Turn 11). The following back straight is the longest in MotoGP at 1.2km and ends with the hardest braking on the calendar, from over 330km/h to less than 60km/h.

Maverick Vinales has withdrawn from the COTA event after the tragic death of his young cousin Dean Berta Vinales in last weekend's Jerez WorldSSP300 race...

Austin MotoGP, COTA - Free Practice (1) Results
1Marc MarquezSPARepsol Honda (RC213V)2'15.872s12/15338k
2Jack MillerAUSDucati Team (GP21)+0.167s14/15339k
3Johann ZarcoFRAPramac Ducati (GP21)+0.599s16/16338k
4Miguel OliveiraPORRed Bull KTM (RC16)+0.783s14/15334k
5Pol EspargaroSPARepsol Honda (RC213V)+0.950s14/15339k
6Alex MarquezSPALCR Honda (RC213V)+1.092s16/16333k
7Alex RinsSPASuzuki Ecstar (GSX-RR)+1.155s15/15334k
8Francesco BagnaiaITADucati Team (GP21)+1.456s16/16338k
9Brad BinderRSARed Bull KTM (RC16)+1.724s13/14336k
10Iker LecuonaSPAKTM Tech3 (RC16)+1.724s16/16328k
11Luca MariniITASky VR46 Avintia Ducati (GP19)*+1.883s12/13335k
12Joan MirSPASuzuki Ecstar (GSX-RR)+2.031s9/14333k
13Danilo PetrucciITAKTM Tech3 (RC16)+2.211s11/14332k
14Aleix EspargaroSPAAprilia Gresini (RS-GP)+2.215s14/14333k
15Fabio QuartararoFRAMonster Yamaha (YZR-M1)+2.293s16/16334k
16Takaaki NakagamiJPNLCR Honda (RC213V)+2.420s14/15338k
17Franco MorbidelliITAMonster Yamaha (YZR-M1)+2.658s13/14329k
18Enea BastianiniITAAvintia Ducati (GP19)*+2.776s14/14335k
19Jorge MartinSPAPramac Ducati (GP21)*+2.960s8/14332k
20Valentino RossiITAPetronas Yamaha (YZR-M1)+3.796s14/14333k
21Andrea DoviziosoITAPetronas Yamaha (YZR-M1)+4.684s5/12329k

* Rookie
Official COTA MotoGP records:
Best lap:
Marc Marquez SPA Honda 2m 2.135s (2015)
Fastest race lap:
Marc Marquez SPA Honda 2m 3.375s(2014)

By Peter McLaren