Robinson faces ankle scan while Glamorgan hit back

Kiran Carlson is Glamorgan captain in the One-Day Cup and vice-captain for the Champoionship side

Marnus Labuschagne and Kiran Carlson hit centuries as Glamorgan fought hard to take the match against Sussex into a fourth day.

Labuschagne made 138 in his final county innings before Australia duties, and acting captain Carlson is on 187.

Sussex were hindered by the absence of England paceman Ollie Robinson, who did not re-appear after lunch because of an ankle problem.

Sussex coach Paul Farbrace revealed that Robinson, who bowled a wicket-less eight over spell, will undergo a scan to identify the problem ahead of the Ireland Test and Ashes series.

In his first Championship match in charge, Carlson out-scored his illustrious partner, striking 18 fours and two sixes to finish four short of his career-best as he took the game to Sussex.

Labuschagne hit 16 fours and four sixes but faced 244 balls in all as he mixed watchful defence with occasional flurries of violence, adding 288 for the fourth wicket.

It was easily a record for Glamorgan against Sussex, beating the previous best stand of 161 by Sir Viv Richards and Tony Cottey in 1990.

The weather and the cricket were of high quality early on as Robinson charged in down the slope and Labuschagne dug in to start the rescue effort.

Spinner Jack Carson made the day's first breakthroughs with a superb stumping from Oli Carter to get rid of debutant Zain Ul Hassan after a mature knock of 43 as a stand-in opener, just lifting his back heel as he went for a slog-sweep.

Sam Northeast fell lbw first ball as Carson turned one just enough, and the young Northern Irishman then had Robinson come on at the other end to ramp up the pressure.

Carlson was dropped at slip off Robinson on three and blasted a return chance through Carson's fingers on 21, while Labuschagne reached his 50 with a slog-sweep six off left-arm spinner James Coles.

The century partnership came up just before lunch, and Glamorgan were remorseless with the bat in the afternoon session as Robinson's absence left Sussex's seam attack short-handed.

The new ball failed to make an impression and Carlson in particular was positive against the spinners as Glamorgan added a further 153 runs in the second session.

Labuschagne smashed a couple of straight boundaries off Carson after tea but fell to batting hero Coles who won an lbw shout with the first ball of a new spell.

Glamorgan were only 53 ahead at that point, but Carlson and Billy Root added 63 before Root was caught at short-leg for 26 off Coles to revive home spirits.

Chris Cooke, who had not kept wicket because of a groin injury, saw out the final half-hour with Carlson.

Glamorgan's Marnus c