Amazing Spider-Man (1963 1st Series) #348

"Righteous Sand" Guest-starring the Avengers. Script by David Michelinie. Pencils by Erik Larsen. Inks by Randy Emberlin. Cover by Erik Larsen and Randy Emberlin.

In Avengers 329 both the Sandman and Spider-Man became reserve members of Earth's Mightiest Heroes! And while the web-slinger isn't overly concerned about gaining the acceptance of his new teammates; the Sandman sure is! So when William Baker (aka Flint Marko) gets a tip about a train hijacking at the Brooklyn railyards; he quickly calls the Avengers! And as expected Cap, Thor, and company (along with the web-slinger) make short work of the heavily-armed saboteurs! But for the Sandman the victory is bittersweet. His days with the Avengers may be over.