Colorado Rockies: Top 50 Rockies of All-Time 30-21
25. Jason Jennings (Rockies Career WAR 10.4)
Jason has the all-time best big-league debut for a Rockies pitcher, and arguably any Rockie of all-time. This is the box score from that debut:
9.0 IP, 5 H, 8 SO, 4 BB, 0 ER, W.
What makes this even better is it was done on the road in New York. He never truly lived up to the hype that debut created (seriously though, it’s asinine to expect anyone to keep that up over the long haul when they are not a Clayton Kershaw/Max Scherzer type).
He was, however, a workhorse, mid-rotation starter who outside of his rookie year and one injury-plagued year late in his Rockies career, never pitched less than 181 innings and stands 4th all-time on the Rockies wins list with 58.
His best year came in 2006 when he won 9 games, struck out 142 and an ERA of 3.72 in 185.1 IP for an ERA+ of 130 and 5 WAR. That’s All-Star level play and what gave the Houston Astros enough confidence to cough up prospects such as 6’8″ righty Jason Hirsh that off-season to get him.