On-base plus slugging (OPS) is a sabermetric baseball statistic calculated as the sum of a player's on-base percentage and slugging average. The ability of a player both to get on base and to hit for power, two important offensive skills, are represented.

Answer this question based on the passage: what does opie s stand for in baseball stats? Okie... think carefully first, then make a decision:
To answer the above question, the relevant sentence is: On-base plus slugging (OPS) is a sabermetric baseball statistic calculated as the sum of a player's on-base percentage and slugging average. So, the answer is On - base plus slugging.