AS Trencin 0-0 Hull City
Tom Huddlestone had a penalty saved as Hull City drew against AS Trencin in Slovakia on their European debut.
The Tigers joined the Europa League third qualifying round after finishing runners-up in the FA Cup and were pushed all the way by the hosts.
But they will be disappointed not to have won the first leg with Huddlestone compounding his penalty miss by hitting the crossbar with the rebound.
The second leg will be played at Hull's KC Stadium on Thursday, 7 August.
Hull, celebrating their 110th anniversary this year, had never qualified for European competition before reaching last season's FA Cup final, which they lost 3-2 to Arsenal.
In order to qualify for the group stages, they will now have to beat Trencin at home - and then win the play-off round.
Steve Bruce picked a strong team, with three at the back, and they started well in Zilina's Stadion Pod Dubnom, 50 miles from Trencin's stadium, which does not meet Uefa requirements.
Full-back Liam Rosenior delivered a superb ball from the left to pick out Shane Long in the 28th minute, but the striker could not find the target with his header.
The hosts then took control of the game.
Trencin continued to test the visitors and Haris Hajradinovic called goalkeeper Allan McGregor into action with a left-footed free-kick on 40 minutes.
The second half continued in a same pattern.
Patrik Misak came within inches of opening the scoring in the 54th minute, with a long-range effort that flew past McGregor's post.
Hull had their big chance when Long was fouled in the 63rd minute.
But Huddlestone - who missed in the shootout when Tottenham lost to Basel in the 2013 Europa League - saw his kick saved by Volesak and then fired the follow-up against the crossbar.
Soon after that double miss, summer signings Robert Snodgrass and Tom Ince came on for their Tigers debuts but they could not make a telling contribution.
Trencin substitute Tomas Malec fired over on the volley from 12 yards with seven minutes to go as Hull held on.
Hull boss Steve Bruce: "You'd have put the house on that Tom would score. It was easier to score.
"We've missed our last three or four penalties, I think, so we better start practising because we're not very good at them.
"We needed a game like this. I was always a bit worried we'd be undercooked a bit. It was always a big ask."
AS Trencin: Volesak, Cogley, Ramon, Klescik, Rundic, Kubik (Malek 67), Hajradinovic (Opatovsky 87), Lobotka, Misak (Mondek 83), Moses, Holubek.
Subs Not Used: Semrinec, Skovajsa, Baris, Madu.
Booked: Misak, Hajradinovic.
Hull: McGregor, Chester, Davies, Bruce, Elmohamady, Meyler (Snodgrass 65), Huddlestone, Livermore, Rosenior, Aluko (Ince 65), Long (Jelavic 86).
Subs Not Used: Harper, McShane, Boyd, Sagbo.
Booked: Huddlestone, Livermore, Davies.
Referee: Davide Massa (Italy).