A last-gasp Jason Kerr winner at Fir Park was enough to hand St Johnstone their first win in five Ladbrokes Premiership matches.
Both teams came into this game desperately seeking a much-needed three points – Motherwell were without a win in five games, while the visitors had lost their previous four.
And when Kerr rose high to head Liam Craig’s corner in added time, it earned a 1-0 victory and a deserved three points for the Perth team.
Saints manager Tommy Wright – who saw his team thumped 6-0 by Celtic in their last outing – matched Motherwell’s 3-5-2 formation in Lanarkshire and saw his team start brightly.
A mix-up at the back between Trevor Carson and team-mate Tom Aldred gifted Saints the game’s first real chance in the 10th minute – but David McMillan’s tame effort from the edge of the box was easily saved by Carson.
Tony Watt then tested Carson again moments later, holding off Charles Dunne and unleashing a fierce low shot from a tight angle on the right that the goalkeeper did well to save.
Saints keeper Zander Clark did brilliantly to keep out Andy Rose’s goalbound header, from David Turnbull’s whipped free-kick in the 16th minute.
Both teams were forced into first-half substitutions, with Motherwell’s Richard Tait replacing Aaron Taylor-Sinclair after the wing-back suffered a knock in the 24th minute, before Chris Kane came on for David McMillan five minutes later.
Motherwell midfielder Turnbull looked the most likely for the hosts, beating two Saints players to tee up Allan Campbell on the edge of the box before the break – but Campbell could only shoot high over the bar.
Turnbull picked up where he left off after the restart, this time feeding Curtis Main through on goal on the left, only for the striker to blast his angled shot over from 10 yards.
Main went close again in the 51st minute with a left-foot curler from distance that dropped just wide of Clark’s far post – and the big striker’s frustrations were clear to see.
Beyond this speculative effort, it was largely a turgid second half short of quality going forward, with an abundance of hit-and-hope long balls.
Motherwell introduced Elliot Frear and Danny Johnson for Main and the ineffective Chris Cadden but it was the visitors that looked the most likely late on.
Substitute Kane saw a deflected cross cleared off the line by Peter Hartley before Drey Wright drilled a low effort towards the bottom corner that was brilliantly saved by Carson.
The visitors continued to press, with Murray Davidson’s shot deflected over the bar and another long-range Wright effort dropping narrowly wide in the final few minutes.
In the end, the pressure paid off as Hartley deflected the ball behind and Carson could do nothing as Kerr smashed the ball into the back of net from Craig’s pinpoint corner.