A dreadful error by Tottenham keeper Radek Cerny meant Spurs made hard work of beating Slavia Prague in the first leg of their Uefa Cup last-32 tie.
Robbie Keane scores Tottenham's second goal
Spurs went ahead when Dimitar Berbatov slammed home from the edge of the area and Robbie Keane slotted in a second before Tom Huddlestone hit the bar.
But the game changed when Cerny dropped David Hubacek's cross, allowing David Strihavka to bundle the ball home.
Erich Brabec headed against the bar for Slavia but Spurs hung on to triumph.
Such a frantic finish seemed unlikely from the way both sides had started the game, with Tottenham well on top.
In front of a sparse crowd at the cavernous Stadion Evzena Rosickeho, Slavia started nervously, stood off Juande Ramos's side and paid the price.
Brabec stopped Jenas on the edge of the box but the ball fell for Berbatov who steadied himself before drilling a superb low first-time shot into the bottom corner of the net.
The home side are top of the Czech league but have not played for almost two months due to a winter break and their lack of recent match practice was painfully apparent in the early stages.
Seemingly without breaking sweat, Spurs' second goal arrived on the half-hour mark when Jenas found Keane in space on the left-hand side of the area and he ran on to slot home past the on-rushing goalkeeper.
The goals could easily have kept coming and only an excellent double save from Martin Vaniak - who kept out a ferocious volley and got up to keep out the follow-up - stopped Berbatov from adding to his tally.
More chances followed either side of half-time as Huddlestone's long-range effort was pushed away by Vaniak before the midfielder smashed a shot against the angle after ghosting past Ladislav Volesak.
Slavia did at least tighten up defensively in the second half but they were still creating little until Cerny's mistake.
Playing against his former club, the Spurs keeper made a hash of Hubacek's deep cross and Strihavka pounced to pull a goal back.
Spurs were still looking good going forward and only a flying save from Vaniak kept out Berbatov's curling free-kick.
But by now the momentum was with Slavia and they pushed forward in search of an equaliser.
Strihavka threatened again, pulling his shot just wide from a narrow angle after getting the better of Jamie O'Hara down the right.
And Brabec went even closer, heading against the bar from six yards after rising unmarked in the box.
Tottenham striker Robbie Keane:
"We controlled the play in the first hour but became quite nervous and could have achieved a better result.
"We allowed Slavia to react and find a way back and now we have a tough second leg to play.
"We could have achieved a more definite win but we can't change it now."
Slavia Prague: Vaniak, Drizd'al, Latka, Brabec, Hubacek, Suchy (Volesak 83), Tavares, Jarolim (Kalivoda 59), Jaroslav Cerny, Pudil (Ivana 46), Strihavka.
Subs Not Used: Vorel, Sourek, Belaid.
Booked: Hubacek, Ivana, Tavares.
Goals: Strihavka 69.
Tottenham: Cerny, Tainio (O'Hara 59), Woodgate, Zokora, Chimbonda, Lennon, Huddlestone, Jenas, Malbranque, Berbatov, Keane (Bent 66).
Subs Not Used: Robinson, Lee, Kaboul, Taarabt, King.
Booked: Tainio, Jenas, O'Hara.
Goals: Berbatov 4, Keane 30.
Ref: Claudio Circhetta (Switzerland).
BBC Sport Player Rater man of the match: Tottenham's Dimitar Berbatov 8.29 (on 90 minutes).
• Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.