Australia's star batsman Steve Smith has been ruled out of the third Ashes Test beginning on Thursday after suffering concussion, Cricket Australia announced Tuesday.

The 30-year-old - who has scored two centuries and 92 in his three innings in the first two Tests - was felled by a Jofra Archer bouncer on Saturday in the first innings of the second Test at Lord's.

The team doctor Richard Saw had the final say on whether Smith played or not and he was seen speaking with him during team training Tuesday.

Smith, whose two centuries in the first Test were pivotal in Australia taking a 1-0 lead, returned to bat on Saturday despite the blow to the side of the head that felled him. He added 12 runs before being out.

However, he was unable to play on the fifth and final day on Sunday as he awoke feeling "groggy." Australia held on to draw the Test with his concussion substitute Marnus Labuschagne playing a key innings.

The Ashes series is the first being played under the International Cricket Council's new concussion substitute regulations, as part of the inaugural World Test Championship.

The regulations allow players who have suffered head or neck injuries to be replaced fully by a substitute, who was previously restricted to fielding alone.

During Saturday's play Smith was wearing a helmet without the additional stem guard neck protection introduced following the death of his former Australia teammate Phillip Hughes who was hit by a bouncer in a domestic Sheffield Shield match in Sydney in 2014.