When the Texans went to bed Thursday night, they thought they had a deal to re-sign free-agent tight end Joel Dreessen.

Dreessen must have dreamed about returning to Colorado, his home state, becoming a starter for the Broncos and catching a lot of passes from Peyton Manning.

When he awakened Friday morning, Dreessen informed the Texans he would be signing with the Broncos. He got a three-year deal worth $8.5 million.

Dreessen, 29, was an all-state player at Fort Morgan, Colo. He played at Colorado State. The lure of starter’s money and a chance to go home and play with Manning were too good to pass up.

Dreessen’s departure means James Casey and Garrett Graham will compete for playing time behind starter Owen Daniels. Casey, who’s also the only fullback on the roster, figures to get a lot more playing time with the durable and dependable Dreessen out of the picture.

A few hours after Dreessen told Denver executives he would be signing with them, the Broncos agreed to a contract with another free-agent tight end, Jacob Tamme, who played with Manning in Indianapolis. In 2010, Manning’s last healthy season with the Colts, Tamme caught 67 passes for 631 yards and four touchdowns.

Dreessen, who played the last five seasons with the Texans, and Tamme will fill a huge need for the Broncos. They elected to sign Tamme rather than former Colts starter Dallas Clark, who was one of Manning’s favorite targets for years. But Clark has battled injuries the last couple of years, and they went for the 27-year-old Tamme.

Because they play two tight ends at the same time so often, the Texans looked at Dreessen as a starter opposite Daniels. Dreessen caught 28 passes, including six for touchdowns, last season when Daniels led the team with 54 receptions.

Dreessen also excels on special teams. And he can be a deep snapper.

Dreessen’s departure means the Texans have lost four players in free agency. He follows outside linebacker Mario Williams (Buffalo), guard Mike Brisiel (Oakland) and cornerback Jason Allen (Cincinnati).

Linebacker DeMeco Ryans (Philadelphia) was traded. Offensive tackle Eric Winston (Kansas City) and fullback Lawrence Vickers (Dallas) signed with other teams after being waived for salary cap purposes.

Quarterback Matt Leinart, another cap casualty, hasn’t signed with another team.

The Texans have re-signed running back Arian Foster, center Chris Myers and snapper Jon Weeks.

Over the last few seasons, the Texans have been stockpiling depth. Now many of those backup players are inheriting starting jobs, and that depth will have to be replenished in the draft and in free agency after the draft.

john.mcclain@chron.com

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