Paris Saint-Germain routs Bastia
Ibrahimovic has some logic-defying goals during his illustrious career and added another to his collection.
Winger Lucas' cross from the right inadvertently struck Hervin Ongenda and the ball looped up and behind Ibrahimovic, who showed amazing flexibility to volley it over his shoulder with the back of his heel.
Moments later, he made it 2-0 after 15 minutes when Lucas' cross went in off his shoulder.
Cavani replaced Ibrahimovic at halftime and dribbled past three players down the left before slotting in from a tight angle. He added a late penalty for 4-0.
Monaco, the only other unbeaten side, can retain top spot on goal difference if it wins by three goals at lowly Sochaux on Sunday.
Cavani has six league goals so far, one more than Ibrahimovic, although they rarely combine.
PSG coach Laurent Blanc left winger Ezequiel Lavezzi and Cavani on the bench - they played for Argentina and Uruguay respectively midweek in World Cup qualifying - and gave an uncommon rare start to the 18-year-old Ongenda.
Bastia is strong at home but inconsistent away from home and had not won in its previous 25 visits to Paris.
It was soon obvious that bad run was never going to end when Ibrahimovic, who has a black belt in taekwondo, put PSG ahead in the 10th.
''He must have raised his leg about two meters,'' Bastia defender Francois-Joseph Modesto said. ''That's why people pay a lot for players like him.''
If only for one half, Cavani got a chance to play in his favored center forward role, rather than out wide on the right when he's picked in the same side as Ibrahimovic in a 4-3-3 formation.
He missed a good chance when he headed over from Lucas' cross in the 54th, but then scored a brilliant goal of his own that even had a grinning Ibrahimovic leaping up from the bench to applaud.
Picking up Jeremy Menez's pass from the left, he cut inside one defender, rolled the ball past another with great balance, forced goalkeeper Mickael Landreau to go to ground and then calmly curled the ball past another defender on the line from the narrowest of angles.
Landreau dived at Lucas' feet as he went clean through and Cavani hit the post as PSG poured forward.
Landreau then gave away a penalty in the 89th as he came to slide tackle left back Lucas Digne, missed the ball completely, and caught Digne as he tried again to kick the ball. Cavani stepped up to thump the spot-kick home as Landreau guessed the wrong way.