Shakhtar Donetsk battled to a 0-0 draw at Athletic Bilbao as both sides kicked off their Champions League Group H Champions League campaigns at the San Mames Stadium.
Mircea Lucescu's stubborn side refused to give an inch to their Spanish hosts and also posed questions on the counter to remind Bilbao how tricky it can be at this level.
Los Leones, who are back in the group stages for the first time since 1998-99, toiled for long periods against the Ukrainian champions and made a mess of what opportunities did come their way.
A perfect example of that was presented as early as the third minute, when Mikel Rico snatched at a shot after good work from Etxebarria Benat found him in space 12 yards from goal.
The 29-year-old looked rusty as he misjudged how much time he had and poked the ball goalwards before he really had it under control. Donetsk goalkeeper Andrei Pyatov, given the nod ahead of Anton Kanibolotskiy, was relieved to watch it sail harmlessly wide after his defence was cut open with alarming ease.
Once the Ukrainian champions, who have won all eight of their matches so far this season, settled down they started asking questions themselves.
First Taras Stepanenko tested Bilbao keeper Gorka Iraizoz from distance, before Darijo Srna's teasing ball across the six-yard box agonisingly evaded Donetsk's forwards and allowed Iraizoz to desperately scramble it away.
As the first half wore on it became an increasingly tight affair, with Donetsk showing the kind of grit and organisation that perfectly demonstrates why they have only conceded one goal so far this term.
Aritz Aduriz thought he should have had a penalty for the hosts after a clumsy challenge by Yaroslav Rakitskiy, but referee Tasos Sidiropoulos waved away the claims and the match remained goalless at the interval.
Los Leones, who beat Rafa Benitez's Napoli in the play-offs to make it into the group stage, continued to find it hard to fashion opportunities against Donetsk.
Aduriz found himself in the book, possibly as a result of these frustrations, for challenging Pyatov to a lofted delivery into the box.
The former Valencia forward led with his elbow and caught the Donetsk keeper, who was flat out on the ground receiving treatment for some time afterwards.
Donetsk resolute shape offered Bilbao few opportunities, which is why Iker Muniain was left kicking himself when he wasted the best of them with 20 minutes remaining.
The 21-year-old winger did brilliantly to catch the visitors napping in possession and raced away down the left flank in a two-on-one scenario, with Aduriz waiting in the centre, as Donetsk were caught out for numbers at the back for the first time.
But Muniain dithered and gave the Ukrainian side time to regroup before being promptly muscled off the ball - which pretty much typified Bilbao's evening.