Plainfield — Lyman Memorial erupted for five runs in the top of the ninth inning and went on to beat No. 7 Plainfield 7-2 in the second round of the CIAC Class S baseball tournament on Wednesday.

The No. 10 Bulldogs play at No. 2 St. Bernard in Saturday’s quarterfinals at a time to be determined. The teams split their regular season games and the Saints beat Lyman in the Eastern Connecticut Conference quarterfinals to win the ECC Division IV title.

Jared Russo and Mike Incontro had three hits each, Russo tripled and Incontro scored twice. Lyman starter Ben Darrow gave up two hits over 8.1 innings with eight strikeouts. Alex Ortiz got the win in relief.

In other games:

• No. 6 Old Lyme beat No. 22 Old Saybrook, its Shoreline Conference rival, 6-1 in the second round of the Class S tournament. The Wildcats (18-6) will play at another Shoreline team, No. 3 Haddam-Killingworth in the quarterfinals on Saturday.

Old Lyme had a five-run first inning, highlighted by Rowan Meisner’s three-run double. Jordan Hanes followed with an RBI single and David Evers started the scoring when he got hit by a pitch with the bases loaded.

Santiago Rodriguez was the winner, throwing five scoreless innings. Rodriguez allowed two hits with eight strikeouts. Grady Lacourciere, Meisner and Hanes had two hits each for Old Lyme.

• Waterford scored four runs in the bottom of the second inning and held on to beat No. 31 Suffield 6-4 in the second round of the Class M tournament. The No. 15 Lancers (15-9) play at No. 7 St. Joseph in the quarterfinals on Saturday.

Matthew Shampine pitched a seven-hitter for the win, striking out eight. Brian Ingraham had two hits and drove in two runs, Matt Ory singled and scored twice and Roberto Kiefer singled and scored a run for Waterford.