The Mariners signed their last arbitration-eligible player Wednesday when first baseman Casey Kotchman agreed to a one-year, $3,517,500 contract. The salary represents a compromise at the precise midpoint between the arbitration filings of each side ? Kotchman's $3.9 million request and the Mariners' $3,135,000 offer. Kotchman earned $2,885,000 last year.