Oxfordshire's Tim Henman suffered a spectacular collapse as he lost to home favourite Paradorn Srichaphan in the quarter-finals of the Thailand Open yesterday.

Henman edged the first set via a tie-break and although eighth-seed Srichaphan took the second, the Briton was far superior for most of the decider.

However, from 5-2 up Henman capitulated, losing four of the next five games, failing to serve out for victory at 5-3, and eventually losing 7-6, 4-6, 6-7.

Henman, 32, was the only unseeded player remaining in the quarter-finals, but it is Srichaphan, who will meet top-seed Ivan Ljubicic in today's semi-final.

Henman started more brightly and broke Srichaphan in the first game and held serve in the next.

Srichaphan wasted a break point having stretched the Englishman all over the court, but a double fault by Henman handed him the game to draw it level at 3-3.

Serving to stay in the set, another double fault undermined Henman's challenge and Srichaphan's sublime volley won him the next point. Henman produced an excellent shot at the net to end an impressive rally and level the set to go into a tie-break.

Several over-ambitious shots were costly for Srichaphan as Henman went 5-2 up thanks to a perfect backhand before going on to take the set.

Henman went 2-1 up in the second set after Srichaphan wasted a break point with a poorly-struck drop shot. However, Srichaphan broke the Englishman and took a 5-3 lead before closing out the set.

An inspired backhand was beyond the diving Sri- chaphan and gave Henman the first break of the third set to go 2-0 in front.

Srichaphan held serve to win his first game of the set before Henman comfortably moved into a 5-2 lead, looking to close out the match.

Facing defeat, Srichaphan earned a stay of execution by holding serve and pulling back to 5-3. Srichaphan saved his best tennis for the latter stages and capitalised on a break point to prevent Henman serving out the match.

Srichaphan continued his late flurry to level the set at 5-5.

Henman's capitulation saw him produce another double fault as the Thai No 1 went on to earn another break point which Henman saved before taking the game to edge in front again.

Srichaphan held serve to take the deciding set into a tie-break.

And the deflated British No 2 provided little resistance as Srichaphan won the tie-break to condemn him to a 7-6, 4-6, 6-7 defeat.