Thiem 1.56, Monfils 2.74
Thiem has won all 4 of their previous meetings. Their only 2017 match was in March in Indian Wells. He won in straight sets.
Even though Monfils missed a lot of 2017 his hard court results were strong. He won 14 of 20 in 2017. Thiem won 19 of 32.
Thiem has not lost a set so far. He was only broken once in each of his last 2 matches.
Monfils has a really strong record in Doha. He has not played there since the 2014 season when he made the final and took Nadal to 3 sets. He also reached the final in 2012. He has served well all week although took a while to find his timing in the first round against Lorenzi.
I think this goes to 3 sets so we have value on Monfils. Lay Thiem if he breaks first or wins set 1