On Friday at Ospreys Sale led 28-13 at the interval, bemoaned some of the decisions made by referee Craig Evans and admitted the loss was a big disappointment, but he also praised Ospreys for their second-half fightback.
"I think we probably thought we had the match put to bed at half-time," said Diamond. "But fair play to the Ospreys they came out second half and ran everything and probably deserved to win in the end.
"It doesn't help that the referee gives us two yellow cards (Ross Harrison and Marc Jones) in the last 10 minutes and they are collapsing mauls all over the show and we don't get any reward for it.
"But it's the first game we have lost in eight weeks so it's not all doom and gloom.
"I was impressed with the way we got four tries in the first half and then got a fifth, but then we went off the boil defensively."
Sale Sharks return to Aviva Premiership action this Friday evening when they entertain Gloucester at the AJ Bell Stadium. Tickets are available for the game and can be purchased by phoning 08444-994-994 or by booking online at http://www.salesharks.com/tickets/individual.php . If you require more information about booking please email firstname.lastname@example.org.