Glamorgan's bowlers made the most of helpful conditions as Kent's batsmen were restricted on the first day of their LV= County Championship Division Two match at the SWALEC Stadium.
Despite winning the toss, only captain Rob Key really dominated the home attack with 63, although Ben Harmison, who scored 33, and 42 from Adam Ball held Glamorgan up for more than 20 overs after tea before both fell to Michael Hogan.
The visitors closed on 236 for eight with Hogan claiming three wickets while Jim Allenby and Andrew Salter each took two.
Kent handed Fabian Cowdrey his championship debut with vice-captain Sam Northeast having been rested, while seamer Robbie Joseph replaced Doug Bollinger, who was ruled out with a sore shoulder.
Kent also decided to play the one spinner - Adam Riley, with news that James Tredwell is going on a month's loan to Sussex to play championship cricket.
By contrast Glamorgan fielded two slow bowlers - Dean Cosker and Salter - for the first time this season.
When Key won the toss in bright sunshine he probably fully expected his team to bat for at least a day and a half on what looked like a typically placid Cardiff pitch.
It looked an important toss, especially in terms of the bigger picture. With Worcestershire and Hampshire racing ahead at the top of the table both Glamorgan and Kent, sixth and seventh in the table respectively, needed to make the most of their game in hand over the leaders.
BREAKTHROUGH! Glamorgan take the new ball on the resumption of play and Hogan strikes with his second ball of the 2nd over, Ball out for 42
— Glamorgan Cricket (@GlamCricket) June 15, 2014
Key would have been satisfied that he and opening partner Daniel Bell-Drummond had negotiated the new ball to reach 74 without loss shortly before lunch.
But gradually the tide turned Glamorgan's way as first off-spinner Salter struck twice either side of lunch to remove Bell-Drummond for 39 and Cowdrey, who showed obvious nerves on his four-day debut as he made just nine before being caught at short-leg by Ben Wright.
And from 131 for two Kent fell victim to swing, as the sunshine was replaced by overcast and humid conditions. Wobbling it around in the atmosphere, the impressive Allenby got the crucial wicket of Key, who completed only his second first-class half-century of the season, before being trapped lbw playing across the line.
That and the demise of Brendan Nash two balls later put Glamorgan in charge and their position was strengthened either side of tea as the conditions became decidedly gloomy.
Before tea Darren Stevens was the victim of a sharp catch at second slip by Jacques Rudolph off Allenby and from the sixth ball after the interval Sam Billings played on to Hogan.
The ball dominated bat to the extent that Kent's run-rate was well below three an over as Harmison and Ball attempted to repair some of the damage.
They played patiently to recover some of Kent's woe but both were dismissed courtesy of the second new ball, which came after bad light had briefly stopped play. Ball was bowled by one from Hogan which nipped back before Harmison was well caught by Will Bragg at short midwicket.
Bad light then struck again with play being abandoned for the day with four overs remaining.