The mystery of Johan Santana's ailment has been found.
Santana left Thursday's game against the Braves in the fifth with what initially appeared to be a shoulder injury, but manager Jerry Manuel set the record straight Friday.
"It’s not the shoulder," Manuel told the New York Times .
Instead, Santana strained the left pectoral chest muscle, which attaches to the shoulder. There are currently no plans for Santana to undergo an MRI and he will instead rest his arm in the hopes he can make a start Tuesday. It's possible Santana may throw on Saturday and test his injury.
In 29 starts, Santana has posted a 2.89 ERA to go along with an 11-9 record. His strikeouts have tailed off, punching out just 6.5 batters per nine innings compared with a career mark of 8.9. His fastball velocity has averaged just 89.4 mph on the season, a career-low after topping out at 93.1 mph in 2006.
With the velocity having decreased for the fourth straight year, questions surrounding Santana have popped up as to whether he is truly healthy or not. The lefty missed the end of the 2009 season with left elbow surgery to remove bone chips, but has been able to outperform his 2009 numbers by reducing the amount of hits and home runs given up.
-- Evan Brunell
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