Bayern Munich coach Pep Guardiola is taking nothing for granted as his players travel to war-torn Ukraine to take on Shakhtar Donetsk.
Shakhtar will be without home advantage, with their Donbass Arena -- which has been badly damaged -- in an area controlled by pro-Russian separatists. The game will be played in Lviv, 600 miles away.
Bayern returned to form at the weekend when they humiliated Hamburg 8-0 at the Allianz Arena.
And anything but safe passage from their tie against Shakhtar would be a huge disappointment to the German champions, who expect to be in Berlin for the final in early June.
Guardiola warned that Bayern would be up against "one of the best teams in Europe" on Tuesday night.
"As the Barcelona coach, I came up against Shakhtar four or five times," he told his prematch news conference.
"They have outstanding central defenders and excellent Brazilian midfielders, very quick players. They have bags of experience in this competition.
"I need to convince my team how difficult this will be. We need to play two great games, but we are ready."
Guardiola said he would not take any risks and would only play Xabi Alonso if the Spaniard is fully fit after he missed the thrashing of Hamburg with a muscle problem.
Jerome Boateng, however, could return after sitting out the last two Bundesliga games through suspension.
"It's pretty bad when you have to sit in the stands, you lose your rhythm. I hope that, should I start against Donetsk, I'll be able to help the team. I would love to start," he told Munchener Merkur.
"They've got an incredibly strong attack, Luiz Adriano is the Champions League top scorer right now. That speaks volumes."
Shakhtar have yet to play a competitive match in 2015, with the Ukrainian domestic season restarting in late February.
Bayern and Shakhtar have previously not met in any European competition, with the Germans having only played an opponent from Ukraine -- Dynamo Kiev -- once before.
Bayern CEO Karl-Heinz Rummenigge echoed Guardiola's sentiments, saying: "The Champions League is really getting going now in the round of 16, and you have to approach the game with respect and maximum concentration.
"We want to get a result that sets us up to reach the quarterfinals."