Essex Head Coach Paul Grayson said he was delighted Mahmood had joined the club.
"I like cricketers who feel they have point to prove to people and he has lots of ability, he's experienced and he's a fit guy who can bowl with good pace as well so we feel Saj will be a real addition to the squad."
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Rather cloudy with outbreaks of rain
The Duchess of Cambridge has praised the "amazing and life-changing" work of children's hospices in a touching and personal letter.
Cloudy, coastal drizzle later tonight. Breezy near the coast