The Roos are 10th but one of three teams on 32 points, which is only six points shy of the top six.
On Saturday, Wanneroo defeated fifth-placed Willetton (7-230) by three wickets in a match that came down to the final two overs at Burrendah Reserve.
The hosts’ captain Matthew Johnston scored a century as Wanneroo’s Mathew Dzodzos led the visitors’ bowling attack with 3-51.
The Roos’ Rob Richards (109) replied with a century of his own while Willetton bowler Alex Hepburn snared match-high figures of 4-37.
On Sunday, Wanneroo (195) fell victim to Claremont-Nedlands (7-216) by 21 runs in the 46th over at Kingsway.
The Tigers’ Daniel Turkich struck 44 as his side’s leading scorer, with Wanneroo’s Jake Fawcett and Jason Parry taking two wickets each.
In the Roos’ chase, opener Mitch McGee impressed with 87, but it was not enough to get the hosts over the line with Claremont-Nedlands bowler Abhishek Kulkarni (4-20) inflicting the major damage.