Mekhala Costello of Blue Hill Country Club shot a sparkling 2-under 69 to grab a two-shot lead after the first round of the 121st Massachusetts Women’s Amateur Championship in Williamstown.

Westford’s Morgan Smith, the 2002 champion playing out of Mt. Pleasant Golf Club, was second after carding an even-par 71 at Taconic Golf Club, which is hosting the tournament for the first time.

In third was Carys Fennessy of Youth on Course/Mass Golf with a 72. Tying for fourth were Shannon Johnson of Thorny Lea (73) and Allison Paik of The Cape Club of Sharon (73).

Last week, Morgan Smith and her sisters Molly and Maddie made history at the U.S. Women’s Amateur in Tulsa, Okla., by all playing in the national tournament. On Monday, Molly Smith shot a 74 for sixth, while Maddie Smith fired a 77 to tie for 11th.

Tuesday will feature the second day of stroke play before the low 32 golfers qualify for match play.