Baseball is a numbers game. Always has been. Always will be. And here are a few notable numbers for the opening week of the season: March 31-April 7.

15    Earned runs allowed last Sunday by reigning Cy Young winners

Trading baseball players between teams has been part of the charm of the game since the 1800s. Ornery players traded after disputes with managers, struggling players traded for one another in hopes that a change of scenery will bring life back to their game, aging stars traded for young prospects, pitching traded for hitting, difficult contract negotiations avoided by trades, financially embarrassed teams trading players for cash — the game has seen all kinds of reasons for swapping players.