Caddick has taken 68 wickets this season for Somerset

Somerset made certain of promotion to Championship Division One with a 299-run home victory over Glamorgan.

Andy Caddick took 4-48 but their eighth win of the season was sealed when James Harris was caught off Ian Blackwell as Glamorgan were all out for 199.

Justin Langer had earlier declared Somerset's innings on 329-9 after Neil Mckenzie top scored with 84.

Robert Croft took 5-102 for Glamorgan and now needs only five more wickets to reach 1,000 in first-class cricket.

Somerset were in no obvious hurry at the start of play after resuming on 163-3 as McKenzie set about the task of extending the lead and boosting his own chances of being offered a return contract for next summer.

Overnight partner James Hildreth was run out by Richard Grant's direct hit at the non-striker's end for 69, and Mckenzie's own innings came to an end when he was caught by Andrew Davies off Croft on the square leg boundary as he looked for a 13th four.

Blackwell added impetus with 42 off 39 balls, but Croft removed both him and Peter Trego (41) with the help of catches from Jimmy Maher, the first at slip and the second short mid-wicket, before completing his five-for when Craig Kieswetter holed out at long-on.

Langer eventually decided enough was enough with his team 498 runs ahead and it was then a question of whether the young Glamorgan side could survive into the final day.

The odds were against them when Caddick dismissed both openers with the help of keeper Kieswetter, who went on to take five catches in the innings.

Maher (39), Ben Wright (39) and Croft (38) made useful contributions but no-one was able to build a sizeable partnership in the face of some tight Somerset bowling.

Croft's downfall, caught by Hildreth at second slip off Caddick, sparked a rapid end to proceedings as the last three wickets went down for 18 runs, with Alex Wharf unable to bat.

"This was a great victory for us...we planned for this, executed these plans perfectly and controlled this game from start to finish," Langer told the Somerset website.

"We are a good side, have been playing fantastic cricket and have got a good momentum going this season.

"The trademark of a good side is to win games that you are expected to - for us to beat Glamorgan in the way that we have is another good sign for the club."