ARSENAL boss Arsene Wenger bemoaned poor refereeing decisions as his side let a two-goal lead slip in a thrilling London derby with West Ham.<br /><br />Goals from Robin van Persie and William Gallas sent the Gunners on their way before a strike from Carlton Cole and an Alessandro Diamanti penalty earned the Hammers a much-needed point.<br /><br />But frustrated Wenger felt aggrieved with two key decisions – to award West Ham a free-kick that led to their first goal and the spot kick which brought them level.<br /><br />“It is disappointing because we had a good game and get away with the minimum. I believe we were a bit unlucky today with decisions and in their kind of circumstances West Ham did fight for their life and made it very difficult,” he said.<br /><br />“We had plenty of opportunities in the second half and in the end when the other team comes back to 2-1 and any little decision goes against you, you can pay for it.”<br /><br />Although West Ham remain second from bottom, manager Gianfranco Zola was delighted with his team’s fightback, hailing their determination. <br /><br />“I said in the changing room at half-time I saw they were willing to react and that was the difference really,” he said. “I’m pleased and proud for them.”<br /><br />A Robert Green error handed Van Persie an easy opener – the keeper’s collision with team-mate James Tomkins allowing the Dutchman to tap in. Van Persie then turned provider as Gallas powered in a header from his corner to double their lead. <br /><br />But the introduction of Diamanti sparked West Ham into life and it wasn’t long before Cole pulled one back after keeper Vito Mannone could only parry the Italian’s free-kick.<br /><br />Alex Song then upended Cole and Diamanti put the spot kick away. And the Hammers held on despite losing skipper Scott Parker to two yellow cards with five minutes remaining.