The Iron lost 3-0 to Doncaster Rovers in Sky Bet League One on Saturday afternoon.
Doncaster took a 2-0 lead in the opening ten minutes after goals from Ben Whiteman and Herbie Kane.
In the final five minutes at the Keepmoat Stadium, John Marquis confirmed Rovers’ victory, making it 3-0.
Manager Stuart McCall made two changes to the team line-up from last weekend’s defeat against Gillingham. Jordan Clarke, returning from a shoulder injury, and Andy Dales started for the Iron, in replace of Cameron Burgess and Kyle Wootton.
The hosts came forward in the opening five minutes when James Coppinger back-heeled the ball to Kane, but defender Charlie Goode made a double block, before Rory McArdle also prevented a shot.
Just one minute later, however, the hosts went 1-0 up via a deflection. Mallik Wilks cut the ball back to Whiteman, striking the ball from 25-yards out and with the help of a deflection, it flew past Alnwick into the target.
It was soon 2-0 to Doncaster when Kane pounced on a loose ball and went through one-on-one with Alnwick. The winger chipped the ball over the goalkeeper with the ball bouncing into the back of the net.
Rovers came looking for a third in the 13th minute when Danny Andrew hit a driven shot at the goal. However, Goode was in the right place to head it away.
Whiteman had another effort after good build-up play from the hosts, but Alnwick got down low to gather the shot.
The Iron had a chance to get back into the match when Josh Morris controlled the ball following a flick-on from Lee Novak, but his effort just flashed wide of the right post.
Novak played his part in another Iron attack when he floated a cross from the left side into the box. Matthew Lund met it in the air, however the midfielder couldn’t direct it on target.
After the break, Andrew curled a free-kick towards the back post for the home side, with Tom Anderson heading it into the side-netting.
The Iron were unlucky not to score in the 60th minute when Lund forced Ian Lawlor into a good stop. Yasin Ben El-Mhanni did well on the right-wing to cross the ball into the centre, which Andy Dales knocked down for Lund, whose effort was clawed off the line by the goalkeeper.
Good combination play from Dales and Ben El-Mhanni allowed the former to advance forward and shoot. His low strike was deflected behind for a corner, but that came to nothing.
Still in search for a goal, Cameron Borthwick-Jackson showed great trickery on the left-wing and then sent a dangerous cross into the area. Andy Butler cleared the ball only to Lund, whose powerful shot was deflected wide.
With five minutes to go, Marquis made it 3-0 to Doncaster. The forward worked hard to get on the end of a long ball upfield and he calmly slotted it past Alnwick.
Ben El-Mhanni tried his luck from long range in stoppage time, but his attempt was held by Lawlor. Lund then curled a late free-kick just wide of the away team’s goal.
That was the last action at the Keepmoat Stadium, as the Iron face Bradford City away from home next weekend.
Doncaster Rovers: Lawlor, Cummings, Anderson, Butler, Andrew, Whitman, Kane, Crawford (Rowe, 76’), Coppinger (Blair, 86’), Marquis, Wilks (May, 75’).
Unused substitutes: Marosi, Taylor, Anderson, Amos.
Scunthorpe United: Alnwick, Clarke, Borthwick-Jackson, Lund, Morris (Ugbo, 73’), Dales, Perch, Novak (Wootton, 87’), Thomas (Ben El-Mhanni, 17’), Goode, McArdle.
Unused substitutes: Flatt, Horsfield, Lewis, Burgess.
Referee: Andy Woolmer.
Attendance: 7,969 (819 away).