Luke Procter’s double strike was the only reward for a depleted but hardworking Northamptonshire attack that were made to toil by Glamorgan in Cardiff.
Carlson’s 170 not out was the jewel in the crown of Glamorgan’s 462 for four as he and captain Cooke (133 not out) shared an unbeaten club record fifth-wicket stand of 307.
Earlier in the day, Marnus Labuschagne (77) and Billy Root (45) also recorded a century partnership as Northamptonshire’s bowlers worked hard with little return.
Overnight batsman Labuschagne and Root survived the first hour against a Northamptonshire seam attack without the injured Gareth Berg. Sanderson and Procter both proving impressive, beating the edge without luck.
Despite a number of balls beating the bat, Labuschagne looked relatively untroubled and his shots grew increasingly aggressive, so it was a surprise to home supporters when he was clean bowled by an excellent Luke Procter delivery for 77 when looking to leave.
Root followed him in the same fashion and in the same over when he chopped on for 45 attempting to play a cut shot when the ball was too close to his body.
Carlson and Cooke took Glamorgan past Northamptonshire’s first-innings total of 215 and into the lead after lunch as they built on their top order’s good work.
Carlson did edge Kerrigan for four between wicketkeeper and slip, but he and Cooke were otherwise on top on an increaingly flat wicket, even though there were two brief stoppages for rain. Carlson went to 50 from 81 balls with seven fours, but after the second break he was dropped off his own bowling by Rob Keogh who delivered nine overs with Berg on the sidelines.
Soon, Carlson and Cooke’s partnership was worth 100 with the latter bringing up his 50 from 87 balls. Glamorgan went to tea on 295 for 4 and in control. Northamptonshire took the new ball for the third session, but Carlson remained unperturbed as he went to his third century of the season from 151 balls with a four off Procter through the leg side.
Cooke was dropped on 79 off the bowling of Sanderson by Kerrigan at point which summed up the visitors’ day. It allowed the Glamorgan wicketkeeper to reach three figures on his own from 186 balls with just four fours.