No he cant beat Sasori, Deidara could keep his distance but Sasori could send all his puppets to take him down e.e he'd by covered by puppets not knowing which way to go ... And will die a slow painful death(Poison)
Deidara mentioned to Naruto that he was no match for Sasori when he was baiting Naruto to attack him. This may have just been to lure him away, but I believe he is telling the truth.
Sasori would win I think. Even when Sasori is using a single puppet he can spit out senbon like no ones business. Deidara has not been shown to be extremely agile so he'd have toruble not getting hit. Deidara's explosives also aren't instant. He has to get clay, chew it up, and wit for it to get done which we've seen time and again takes a good amount of time. In that time Sasori would destroy him. Sasori also has a lot more experience than Deidara and can destroy a whole village on his own like he's done in the past.
Deidara can't handle Sasori. His explosive take too long to be made, and idk how Deidara will avoid, poison gas, senbon, iron sand, well I mean most things that Sasori has. He has over 100 puppets and some that are especially strong. Idk what Deidara can do.