Andrew McGlashan is a deputy editor at ESPNcricinfo
Queensland 152 and 4 for 370 (Khawaja 158*, Peirson 89*) lead South Australia 280 by 242 runs
He says he doesn't worry much about what the selectors do these days, but Usman Khawaja sent a statement as he batted throughout the third day's play at Adelaide Oval to finish unbeaten on 158 to give Queensland a chance of pushing for victory over South Australia.
Khawaja, who should have been given out late on the second day, continued to ride his luck as he survived a gloved pull down the leg side shortly after reaching his century and was then dropped in the gully on 119.
However, he made the most of the fortune as he repelled an excellent Redbacks seam attack on a surface that while flattening out still offered the quicks some assistance for much of the day.
By the close, he and Jimmy Peirson had compiled a fifth-wicket stand of 165 to take the lead to 242 after earlier important contributions from Marnus Labuschagne and Matt Renshaw.
There could yet be a vacancy at the top of Australia's order for the Ashes after Will Pucovski suffered another concussion although Victoria remain confident he will recovery swiftly. Marcus Harris, who is the incumbent alongside David Warner from the end of the India series in January, has been tipped to hold his place if Pucovski is sidelined but Khawaja could make a case for selection even if everyone is available.
Queensland added 165 in the final session after the first two had brought 142 runs with the batters having to work hard to survive. Labuschagne had hit is first ball for four on Saturday, but it was his only boundary in a 179-ball stay which finally ended when he was lbw to the impressive Nathan McAndrew in a manner that has become familiar early in the season.
Renshaw played compactly alongside Khawaja as the pair added 68 either side of the second new ball during the afternoon before he edged the final ball of the session from McAndrew who found consistent movement around the wicket.
At that point Queensland's lead was still only 77 but the evening session went all their way - reward for the hard work when the going was tough. Khawaja went past 150 from 273 balls while Peirson batted as confidently as anyone. The pair took advantage of overs of spin from Lloyd Pope and Travis Head to swell the lead. It will be interesting to see what sort of target Khawaja sets on the final day.