Complex sentence: He battled injuries as a rookie and posted only a 10-13 record despite leading the league in strikeouts, then settled down in 1926 and won the first of a record nine earned-run average (ERA) titles with a mark of 2.51.
Split into simpler sentences: He battled injuries as a rookie and posted only a 10-13 record, despite leading the league in strikeouts. Grove then settled down in 1926 and won the first of a record nine earned run average (ERA) titles with a mark of 2.51.