Nottinghamshire's promotion party fell flat when Michael Munday took 6-34 as Somerset closed in on an innings win.

The leg-spinner's career-best figures left the visitors, who were 311 behind after the first innings, on 147-7.

Munday accounted for Will Jefferson (44), Bilal Shafayat (57), Mark Wagh, Stephen Fleming, Chris Read and Andre Adams as seven wickets fell for 45.

Earlier, Marcus Trescothick, Ian Blackwell and Peter Trego scored centuries to lift Somerset to 469.

Blackwell was the first to reach his ton, off just 91 balls with 13 fours and two sixes, while Trescothick, who had already reached 50 when Blackwell joined him, faced 188 balls before recording his fourth century of the season.

Charlie Shreck ended the partnership on 204 and Trescothick followed six runs later to leave Somerset 310-6 but there was no respite for the bowlers as Trego took up the attack.

He smashed 16 boundaries and two sixes before running out of partners, having shared a ninth-wicket stand of 82 with Steffan Jones, on 113.

Jefferson and Shafayat responded with an opening partnership of 98 for Notts before Munday weaved his magic from the Old Pavillion End.

The 22-year-old took the first four wickets to fall before Blackwell pinned Samit Patel lbw 122-5.