Sandra Day O'Connor liked the number five on Monday. It served the Eagles well in leading the medalist chase and team-title battle after the first round of the Division I boys golf tournament at Grand Canyon University Golf Course.

SDO's Noah Robinson fired a 5-under par 66 to hold the medalist lead after the initial 18 holes. Robinson, a senior, made five birdies and and parred everything else. He and his teammates combined for a 5-under score to hold a 1-shot lead over second-place Hamilton and two shots over third-place Desert Vista.

Robinson has a one-shot advantage over three players -- Campo Verde's Branden Meyer, Perry's Ryan MacPherson and Hamilton's Mason Andersen. Another shot back at -3 are Desert Vista's Tyler Svendson and Boulder Creek's Mason Domecq. Sixteen players are within four shots of the lead.

The final round is Tuesday (Nov. 8). Tee times begin at 8 a.m. for the 90-player field. Most of the leaders are set to tee off between 9:30 and 10:20.