Barcelona and Bayern Munich are goalless at the interval of their Champions League semi-final first leg at Camp Nou, but the home side have had the best of the chances.
Bayern pressed extremely high in the early moments, with Barcelona given licence to counter on a number of occasions.
The home side had a penalty shout inside four minutes when Jerome Boateng seemed to trip Luis Suarez inside the box, but the referee was not interested and Bayern stopper Manuel Neuer was on hand to collect.
Suarez was again involved after seven minutes following a quick counter from the hosts, but the Argentine's effort was straight at Neuer during what was an open start to proceedings.
Suarez had a golden chance to open the scoring after 12 minutes when he ran through on the Bayern goal, but again Neuer was on hand to make the save. The opportunities continued to arrive as Suarez then set up Neymar after 15 minutes, but somehow it trickled wide as the score remained level.
Bayern were next to come close when Thomas Muller slid a super cross into Robert Lewandowski, but the Polish international made a hash of it.
Barcelona remained the biggest threat, however, with Jordi Alba forcing a clearance from Boateng, before Suarez headed over the crossbar from the resulting corner. Thiago then curled one past the post for Bayern down the other end as the score remained level with 30 minutes on the clock.
Barcelona forced a free kick in a dangerous area after 35 minutes, but Messi's effort was collected by Neuer, before the German goalkeeper denied Dani Alves from inside the box.
The home side continued to press in the final moments of the half, but Bayern held strong to keep the score goalless at the interval.