The game started out very even, with Sporting utterly determined to take revenge on Bayern for the result a fortnight ago; however, the home side managed to prove their superiority once again, through Lukas Podolski on seven minutes.
The Bayern striker, who is due to leave the Allianz Arena at the end of the season, got the ball just outside the area after Polga's mistake and fired a powerful shot with his left foot straight into the top corner, with keeper Rui Patrício completely helpless.
Things did not look good for Sporting, who were now down by six goals on aggregate, and Bayern wanted even more and were very close to making it two, 17 minutes into the game. Mark van Bommel's shot from outside the box was denied by Patrício but the rebound fell to Miroslav Klose, who could not do better than hit the post.
Sporting looked fragile and their defence was making the same mistakes they made during the second-half at the José Alvalade. Bayern had two great opportunities in the 28th and 29th minutes; Christian Lell had the first chance but sent his shot over the bar with only the keeper to beat, while Klose could not hit the ball properly in the second.
On 33 minutes, Bayern scored their second to inflict more misery on Sporting. Polga and Patrício collided in the penalty box while trying to clear the ball away from danger and Podolski slotted into an empty net with an overhead kick.
Sporting had their first chance on goal in the 36th minute, when Vukcevic's free-kick shot got deflected but Jorg Butt still managed to save it. And just one minute later, Sporting suffered an own goal as Polga tried to clear the ball but sent it home.
With 39 minutes on the clock, Sporting managed to pull one back. João Moutinho fired a well-placed shot with his right foot from 20 yards out to score his team's first of this last-16 stage.
But there was little time for Sporting to celebrate Moutinho's effort as Bastain Schweinsteiger would score Bayern's fourth goal of the night just one minute later after a cross from the right by Lell.
Sporting looked better after the interval and the proof of that is that Bayern did not have a dangerous opportunity during the first 15 minutes.
In the 61st minute, Izmailov tried his luck from outside the box with a powerful effort but it was punched away by Butt in style.
The away side seemed to be the better team at this moment, Simon Vukcevic had a good opportunity on 67 minutes but he took too long to decide what to do and Bayern cleared the ball away from danger.
But 74 minutes into the game, Bayern scored their fifth. Thomas Müller, who had replaced Schweinsteiger just three minutes before, raced down the pitched and crossed to the far post, Podolski headed to van Bommel and the Dutchman simply took advantage of another mistake by Polga to score for his team.
Seven minutes later, Klose was brought down in the area by Pedro Silva and the referee immediately signalled a penalty. Klose made no mistake although Patrício was very close to denying the sixth goal.
Podoslki could have scored a hat-trick in the 87th minute but the keeper punched it away. From the resulting corner, Müller sent it home from two yards out after some poor defending from Sporting.
Sporting will have thanked the referee for blowing the whistle as the game ended 7-1, 12-1 on aggregate, a result consigned to the history books and that leaves the Portuguese side with low morale for the remainder of the season.
1-0 Podolski 7'
2-0 Podolski 33'
3-0 Polga 37' (OG)
3-1 Moutinho 39'
4-1 Schweinsteiger 40'
5-1 Van Bommell 73'
6-1 Klose 81' (penalty)
7-1 Müller 87'
Butt, Christian Lell, Lúcio (Breno, 45'), Van Buyten, Philipp Lahm, Schweinsteiger (Muller, 71') Ottl, Van Bommell, Zé Roberto (Sosa, 45'), Podolski, Klose.
Sporting Clube de Portugal
Rui Patrício, Pedro Silva, Tonel, Anderson Polga, Miguel Veloso (Abel, 45'); Pereirinha (Izmailov, 45'), Adrien (Caneira, 74'), João Moutinho, Vukcevic, Derlei, Yannick Djaló.
Luís Mira, Goal.com