(changes dateline, updates with Roura quotes) MUNICH, April 22 (Reuters) - Barcelona forward Lionel Messi, who has been struggling with a hamstring strain, is likely to face Bayern Munich in Tuesday's Champions League tie but his participation will be decided after a final training session, the Catalans said on Monday. "I wouldn't like to venture a definitive answer, but in these last few days, the injury has evolved well and we have a good sensation," interim coach Jordi Roura told a news conference. "But we will wait and see what happens in training. ... More...