5) Omar Moreno-5 years, $3.25 million
Houston gave Moreno five years and $3.25 million with hopes the defensive centerfielder could regain some semblance of offensive form.
Moreno didn't regain any offensive form and was traded after only 97 games. In his time as an Astro, Moreno hit .242 with a .608 OPS, the worst year of his big league career.
That the Astros pledged that length of contract to the outfielder before sending him out only one year in was simply astounding. His on field perfomance was subpar and it's rumored he became a bit of a problem in the clubhouse. The $700,000 Houston pledged to Moreno annually couldn't have backfired more than it did.