Indy Pro 2000 champion Sting Ray Robb topped the final qualifying session of the season as he completed a double pole position in St Petersburg.
Robb had been pushed back from first to fifth with three minutes remaining when he posted a 1m07.602s – a new track record.
That left the Juncos Racing driver 0.3274 seconds ahead of second-placed Colin Kaminsky at the end of the session.
Danial Frost was six hundredths of a second behind Kaminsky in third, with Hunter McElrea fourth.
Championship returnee Rasmus Lindh took fifth in front of Artem Petrov and Parker Thompson.
Ninth in Friday’s first qualifying, Devlin DeFrancesco this time took eighth on this occasion as he looks to cling on to second place in the championship.
|1||Sting Ray Robb||Juncos Racing||1m07.602s||11|
|2||Colin Kaminsky||Pabst Racing||1m07.929s||+0.3274s||12|
|3||Danial Frost||Turn 3 Motorsport||1m07.989s||+0.3877s||12|
|4||Hunter McElrea||Pabst Racing||1m08.026s||+0.4240s||14|
|5||Rasmus Lindh||Turn 3 Motorsport||1m08.031s||+0.4291s||11|
|6||Artem Petrov||Juncos Racing||1m08.139s||+0.5375s||11|
|7||Parker Thompson||DEForce Racing||1m08.175s||+0.5731s||14|
|8||Devlin DeFrancesco||Andretti Steinbrenner Autosport||1m08.202s||+0.6006s||13|
|9||Manuel Sulaiman||DEForce Racing||1m08.389s||+0.7876s||14|
|10||Kory Enders||DEForce Racing||1m08.663s||+1.0619s||14|
|11||Tristan Charpentier||Exclusive Autosport||1m08.956s||+1.3549s||12|
|12||Moises de la Vara||DEForce Racing||1m09.005s||+1.4035s||14|
|13||Nate Aranda||Juncos Racing||1m09.704s||+2.1025s||13|
|14||Charles Finelli||FatBoy Racing||1m12.509s||+4.9074s||13|