After watching him pitch in the International Prospect League all-star game on Friday, the Reds have signed Dominican lefthander Jacob Constante for $730,000.

Constante, who turns 19 in March, is 6-foot-3, 215 pounds and threw 92-94 mph with good life on his fastball at the IPL event. He showed solid mechanics for his age and flashed a potentially above-average slider at 80-83 mph. He also threw a below-average 83-84 mph changeup that he had trouble keeping out of the dirt. Constante, who is from Santo Domingo and trained with Rudy Santin, is also already fluent in English.

The Constante signing is the biggest bonus bonus the Reds have agreed to with an international player during the 2012-13 signing period, which began on July 2. The only amateur lefthanders who have signed for more money during the current signing period were Venezuela's Jose Castillo, who signed for $1.55 million with the Rays, and Brazil's Luiz Gohara, who landed with the Mariners for $880,000.