Zaheer's figures were the best of his first-class career

Dogged batting from Ravi Bopara and Ronnie Irani forced Essex's Championship match against Worcestershire into the final day.

And with Essex on 302-4 in their second innings, just 65 runs behind, the hosts retain a chance of forcing a draw.

At the start of the day, all eyes were on Zaheer Khan as he attempted to become the first Worcestershire bowler to take 10 wickets in an innings.

But, with nine out of nine overnight, the Indian star failed in his quest.

Essex had been 186-9 in reply to the visitors 650-7 declared when play began.

But a dropped catch by wicket-keeper Steven Davies allowed Darren Gough to escape and cost Zaheer the clean sweep.

Bopara (67 not out) and Gough (50) took 73 runs off Zaheer's 33 balls in the first hour before Matt Mason took the last wicket with the score on 283.

Bopara and Gough had added 97 for the last wicket.

Zaheer finished with figures of 9-138, the best of his career, and Worcestershire skipper Vikram Solanki enforced the follow-on.