Joe Edwards began his Millwall managerial career with a comprehensive victory at Sheffield Wednesday.
The new Lions manager took charge of his first game at Hillsborough and found the home side in obliging mood as goals from Murray Wallace, George Saville, Wes Harding and Brooke Norton-Cuffy gave the Londoners their first win in six games.
Defeat meant more misery for recently-appointed Wednesday boss Danny Rohl, who saw his side register their first win of the season last week, against Rotherham.
Defeat leaves Wednesday, who were without strikers Michael Smith and Lee Gregory, rooted to bottom spot.
Edwards was appointed as the new manager at The Den last Monday after spending nine years as a youth coach at Chelsea and then as assistant to Frank Lampard at both Stamford Bridge and Everton.
He took his new charges to face a struggling Wednesday side. who have had three managers in six months, with the latest incumbent Danny Rohl already struggling with four defeats from his first five in charge.
The Owls began brightly enough but Anthony Musaba squandered a great chance after fine work from Barry Bannan, and they fell apart after Wallace was left unmarked to head home George Honeyman's corner in the 31st minute.
Wednesday goalkeeper Cameron Dawson had to be alert to prevent Harding doubling the lead but just before half-time, Saville's sweet volley from the edge of the area gave the Lions a two-goal cushion.
Rohl responded by sending on Jeff Hendrick, Josh Windass and Bailey-Tye Cadamarteri, the son of ex-Everton player Danny, who was making his league debut.
Dominic Iorfa headed over the bar as Wednesday sought a way back into the game but it was over as a contest in the 52nd minute when Dawson failed to hold Casper De Norre's cross and Harding snapped up his third goal in four games.
Cadamarteri was denied a debut goal by Millwall keeper Bartosz Bialkowski before Norton-Cuffy eased round Musaba to apply the finishing touch with his first goal for the club.
The win moves Millwall up to 15th, closer to the play-off places than they are to the relegation zone.
Sheffield Wednesday manager Danny Rohl told BBC Radio Sheffield:
"It's hard to find the right words. Again, we started very well with a lot of energy in the group, on the front foot playing forward.
"We had a big chance and missed it, and that was a turning point in the game. We conceded almost immediately and then you had the feeling the guys were thinking about what happened and there was less intensity in our game, our counter-pressing was not what we needed.
"It's a normal process when you are in this position, thinking about having to come back in the game. We tried to change the shape and the players at half-time, but we then conceded a goal again.
"This is football, but it's important that we look forward and go forward, train hard like the last few weeks."
Millwall manager Joe Edwards told BBC Radio London:
"Although it's a new start for me, I'm joining a team that are very much in the thick of things in the Championship and have gone a few games without a win. It was important to start getting points back on the board.
"In terms of a performance, what you want to see from a team is different strengths and qualities coming out, and we saw that today. We dug in when we had to, and were well-organised but with the ball we posed a real threat as well
"We have some big players and when you can deliver the ball like that and find players like Murray (Wallace) in the box, set-pieces are always going to be a weapon of ours and we need to build on that.
"But if you let us in your half and we get composed and comfortable on the ball, we showed we can do some damage as well."