The two-year veteran was waived by the Buffalo Bills earlier this week.
To create a roster spot for Watson, the Texans released rookie linebacker Trent Bray.
Originally selected by the New Orleans Saints in the second round of the 2004 draft, Watson is actually joining his fourth different team in less than four months. He was traded to Miami in May for linebacker Eddie Moore. That deal was nullified, however, when Moore failed his physical exam with the Saints. Watson was then dealt to Buffalo on June 6 for third-year tight end Tim Euhus.
But after a disappointing training camp with the Bills, one in which he failed to secure the backup spot at middle linebacker, Watson was released.
Houston is still shuffling its linebacker corps, seeking backup players for the inside spot, and felt Watson merited another shot at carving out an NFL career. At one point, Watson was regarded as the long-term solution to the Saints' lingering problems at middle linebacker. But he became a short-timer there with the change of coaching regimes. Early in the spring, the Saints gave Watson permission to seek a trade.
It was felt that with a fresh start in Buffalo, Watson might flourish, but that wasn't the case.
The 60th player chosen overall in the 2004 draft, Watson signed a five-year, $2.98 million contract with the Saints. The deal, which included a $1.052 million signing bonus, still has three seasons remaining on it, because Watson was able to void the fifth year.
In 21 appearances with New Orleans in 2004-2005, Watson registered 115 tackles, three sacks and three passes defensed. A sprained knee sidelined him for the final seven games of the 2005 season.
Len Pasquarelli is a senior NFL writer for ESPN.com. To check out Len's chat archive, click here.