Spellshield didn't stop knockback on Azir's Wall.
http://imgur.com/a/B04qY
Sivir was flashed on and as Azir cast his ult she cast spell shield, wall and soldier AUTO(not Q 100% sure) hit at the same time. Positioning of my champion was on Azir and moving away from direction of cast. During collision of spells, spell shield was proc'd mana given; Sivir was pushed back by the wall.
Have Baron Replay file.
Sidenote, soldier auto cannot be spellshielded, but felt I should mention it.