The match kicks off at 5.45pm. Al Nasr, which won the recently-concluded Mazda Professional Cup, is currently placed fourth in the OPL. It drew 2-2 with Sur in its last OPL game and would be looking for a crucial away win before it hosts the return leg on April 17.
Saham, which claimed its only title in 2010, is the latest winner among the four semifinalists in fray on Wednesday.
While Al Nasr has won it four times, its last title triumph was in 2006 and the other two semifinalists - Salalah and Al Khabourah - have never reached that stage in the 44 year old history of the coveted competition.
Al Nasr will not only be wary of its rival on the field, but is also expected to face a good number of hostile Saham fans, who can put pressure on any visiting team.
Saham lost its last OPL match to league leader Al Suwaiq 1-3, but will look to bounce back and upset the in-form team.
Both the teams had similar paths to the semifinals, with Al Nasr shocking Fanja 2-2 in the quarterfinals and advancing on the away-goals rule after having lost the first leg 0-1.
Saham, too, lost to Muscat 1-2 in the first leg, but routed its rival 3-0 in the second leg to advance 4-2 on aggregate. In the other semifinal, to be played at the Al Saada Sports Complex, Khabourah will go into the match high on confidence against hosts Salalah after a big win in its OPL fixture on Sunday.
The match kicks off at 8pm. Both the clubs have reached this stage of the HM's Cup for the first time, with Khabourah upsetting former champion Suwaiq 2-1 in the double-leg quarterfinals.
Salalah had to stave off a tough challenge from Rustaq, advancing through a penalty shootout 5-4 after the teams were locked 1-1.
Both the teams have done well in the competition, though they are languishing in the bottom places in the OPL, with Khabourah placed tenth and Salalah at the pit of the 14-team table.