The last-32 tie at Anfield had been finely poised after last week’s first leg in Bavaria ended goalless and the home side also had one eye on Sunday’s League Cup final at Wembley against Manchester City.
Misfiring Liverpool eventually had to survive some late scares, notably when Augsburg left-back Kostas Stalfydis sent a free kick inches wide with the clock ticking down.
“If you can’t decide a game early enough it’s always nervous,” said Klopp.
“It was a really good game and it everyone who saw it would say we deserved to win.
Later Thursday Louis van Gaal’s Manchester United host Danish champions Midtjylland as they try to overturn an embarrassing 2-1 deficit from the away leg.
While also in England Mauricio Pochettino’s Tottenham Hotspur will be without star striker Harry Kane for their return leg with Italians Fiorentina at White Hart Lane after last week’s 1-1 draw in Italy.
Milner’s slick penalty conversion on five minutes came after Augsburg’s Dominik Kohr handled after his arm got into a tangle with a teammate leaping to head away a shot.
But from then on Liverpool’s enterprising midfield interplay, with Brazilians Roberto Firmino and Coutinho buzzing around the area, failed to carve open any clear cut chances.
Emre Can and Daniel Sturridge were thwarted by injury-hit Augsburg’s packed defence and Sturridge, recently returned after two months out with a hamstring problem, was replaced by Divock Origi on the hour.
Attack after attack broke down in the final third as Klopp raged on the sidelines as Coutinho and Jordan Henderson both frustrated by an excellent Marwin Hitz in the Augsburg goal.
Gary Neville’s Valencia racked up a 10-0 aggregate score with a 4-0 win at Rapid Vienna, Shakhtar Donetsk stunned Schalke 04 with a 3-0 win in Germany while a Karim Bellarabi double for Bayer Leverkusen helped them beat Sporting Lisbon 3-1 on the night and 4-1 on aggregate.
Athletic Bilbao edged Marseille 2-1 after a 1-1 draw in Spain and Lazio beat Galatasaray 3-1 (4-1 on aggregate) to also go into the hat for Friday’s last 16 draw.
— AFP