Pramac Ducati's Danilo Petrucci was fastest in a Sepang MotoGP test disrupted by a massive crash for Loris Baz, and in which Jorge Lorenzo's pace again looked ominous.
Returning MotoGP tyre supplier Michelin withdrew its soft compound and mandated higher tyre pressure after what appeared to be a blowout sent Baz flying at 180mph on the pits straight.
The Avintia Ducati rider escaped with bruising and was able to rejoin the session later.
Petrucci was one of the riders who got in a flying lap on the softs before the incident, setting a 2m00.095s.
With only hards available for the rest of the day, that position looked safe.
But Lorenzo - who had dominated Monday's session - managed to get within 0.06 seconds of Petrucci's pace using hards on his Yamaha in the closing minutes.
That pushed Hector Barbera of Avintia down to third. Marc Marquez, Cal Crutchlow and Valentino Rossi completed the top six.
Lorenzo was one of many riders to crash at Turn 5, with Dani Pedrosa and Pol Espargaro also among those going down at the long left-hander - twice in Espargaro's case. All were unhurt.
In his first session alongside the MotoGP field since retiring at the end of 2012, Casey Stoner went ninth quickest, just behind works Ducati team-mate Andrea Iannone and Pramac rider Scott Redding.
Eugene Laverty sat out Tuesday's session to rest following his huge accident on Monday and went for further scans in hospital at the end of the day to assess whether he can ride on Wednesday.
DAY TWO TIMES:
|1||Danilo Petrucci||Pramac Racing||Ducati||2m00.095s||-||46|
|3||Hector Barbera||Avintia Racing||Ducati||2m00.387s||0.292s||32|
|7||Scott Redding||Pramac Racing||Ducati||2m01.049s||0.954s||42|
|10||Bradley Smith||Tech 3||Yamaha||2m01.107s||1.012s||59|
|15||Pol Espargaro||Tech 3||Yamaha||2m01.992s||1.897s||32|
|17||Tito Rabat||Marc VDS||Honda||2m02.328s||2.233s||54|
|18||Stefan Bradl||Aprilia Gresini||Aprilia||2m02.372s||2.277s||45|
|19||Loris Baz||Avintia Racing||Ducati||2m02.611s||2.516s||26|
|21||Alvaro Bautista||Aprilia Gresini||Aprilia||2m02.876s||2.781s||52|