Sam Konstas’ half-century helped Sydney Thunder thrash Perth Scorchers by 61 runs and seal a place in the Big Bash knockouts.

The 19-year-old, who made his Australia debut in the Test series against India in December, held together Thunder’s innings with 53 from 42 balls.

Wickets fell regularly around him as Thunder slipped to 75-5 and then 101-6 when Konstas was dismissed.

Tom Andrews smashed an unbeaten 37 off 13 balls though to drag Thunder up to a respectable 158-7.

Scorchers were reduced to 48-5 in the powerplay and were unable to recover, eventually being bowled out for 97 in 17.2 overs.

Thunder go top of the table and join Sydney Sixers and Hobart Hurricanes in the knockouts.

Scorchers are now bottom of the table and need to win their final game and hope other results go their way.