George Miller scored twice on his home debut as Walsall cruised to a 3-1 victory that sent Mansfield crashing to a fifth successive defeat.
Miller, a deadline day loan arrival from Barnsley, brushed off Stags defenders to score at the start of each half, while Ash Taylor also netted for the Saddlers before Danny Johnson's late response.
Walsall led after just six minutes, Miller outmuscling Mansfield centre-half Elliott Hewitt to a high ball and drilling past Nathan Bishop from just inside the box.
Miller struck the woodwork with a superb dipping 25-yard volley before Taylor bulleted home a header from Jack Earing's corner to double Walsall's lead on 22 minutes.
Mansfield could have levelled moments before but Saddlers keeper Carl Rushworth did well to tip over Oli Hawkins' glancing header.
Bishop kept Mansfield in it with an instinctive save from Brendan Kiernan's blistering half-volley before half-time but Miller shrugged off Richard Nartey to slide home his second on 48 minutes.
The Stags keeper denied Miller a hat-trick before a free-kick dropped to Stags substitute Johnson to lash home an 84th-minute consolation.