Rob Harley scored a late try as Glasgow Warriors extended their 100 per cent start to the Guinness PRO14 season with a dramatic 29-26 victory over Cheetahs in Bloemfontein.

Flanker Harley crashed over with four minutes remaining following Finn Russell's expert chip to continue the Warriors' fine run and prevent their in-form hosts recording a fourth successive win.

The 76th-minute score also earned the Scottish side a bonus point after Callum Gibbins registered his first two tries for the club and Henry Pyrgos got his name on the scoreboard.

A high-scoring contest was expected at the Free State Stadium and Russell's second-minute penalty put Glasgow ahead, before the hosts roared back to establish a 10-3 lead thanks to Sergeal Petersen's converted try and a penalty from fly-half Ernst Stapelberg.

Flanker Gibbins' first score of the evening, converted by Russell, levelled proceedings but the home side took a seven-point lead into the break after Rosko Specman ran the length of the field to touch down and Stapelberg added the extras.

In an action-packed second period, Glasgow restored parity when Russell converted in the 55th minute after Gibbins had crossed following a fine interception and run from Ruaridh Jackson.

A pair of penalties from Stapelberg swung the advantage back in Cheetahs' favour before Henry's converted try gave Glasgow a slender one-point advantage heading into the final nine minutes.

The Warriors' unbeaten start to the campaign looked in doubt when Stapelberg kicked a 76th-minute penalty to put the South African team back in front but Harley popped up moments later to make it six wins from six for the Conference A leaders.