Charlie Austin struck twice to lift Southampton over AC Sparta Prague 3-0 in the Europa League group stages at St Mary’s.
Southampton boss Claude Puel was rewarded with his first win at the club after making seven changes from the defeat at Arsenal.
Austin scored both goals inside the half-hour mark including from the spot, which gave the Saints an early advantage.
Second half substitute Jay Rodriguez added a third goal in injury time to cap of a dominant victory.
Sparta Prague, who reached the quarterfinals of the competition in 2015/16, remains without a win over an English club in their last 15 attempts (11 L, 4D).
Southampton got off to a flying start after being awarded a fourth minute penalty, which was not initially given, by the assistant referee, who had adjudicated that the ball struck Costa Nhamoinesu on the arm as he slid in for a challenge on Austin at the edge of the box.
After holding off teammate Dusan Tadic on the spot, the former QPR striker stepped up and slotted past a sprawling Tomas Koubek.
Southampton looked immediately to add a second, but Virgil van Dijk could only head over the bar from James Ward-Prowse’s free kick six minutes after the opening goal.
Austin then had a half chance to double the lead on 26 minutes when he stretched to get a foot on James Ward-Prowse’s free kick, but despite getting an attempt on target he was unable to generate any power.
Still in the ascendancy, Southampton again thought they’d scored a second in the 26th minute when Austin’s header hit the back of the net only for the flag to go up on the far side.
But the flagged stayed down seconds later when Austin made it 2-0 as he turned in Martina’s sensational cross.
The Saints continued to make use of the wide areas at the start of the second half, as Tadic cut in from the right before firing a tame left-footed shot into the keeper’s grasp.
Sparta Prague, who had little to show for their visit to the south coast, came close in the 69th minute when substitute David Lafata hit first-time following a deflection, but Fraser Forster parried the shot away.
Jay Rodriguez came off the bench to make it a comprehensive 3-0 scoreline following terrific build-up play, as he directed Shane Long’s pass into the bottom corner in the final minute of added time.
Southampton: Forster, Targett, Yoshida, van Dijk, Martina, Romeu (Davis 83), Hojbjerg, Ward-Prowse, Tadic (Redmond 69), Long, Austin (Rodriguez 77).
Unused subs: McCarthy (GK), Bertrand, Fonte, Clasie.
Goals: Austin (4, 27), Rodriguez (92).
Sparta Prague: Koubek, Kadlec, Costa, Holek, Vacha (Marecek 64), Frydek, Sural (Pulkrab 74), Sacek, Karavaev, Julis (Lafata 46), Kadlec.
Unused subs: Bicik (GK), Mazuch, Cermak, Holzer.
Bookings: Kadlec, Pulkrab.