Tight end Jason Witten is expected to miss the rest of the preseason and possibly even longer with a serious abdominal injury he suffered in the preseason opener in Oakland Monday.

Witten had further tests and examinations on Tuesday, after discovering an injury to his spleen area. The Cowboys weighed the option of possibility of surgery, which would’ve likely ended his season.

Instead, the Cowboys are hopeful Witten can be ready for the Sept. 5 opener against the Giants.

It appeared the injury occurred in the first quarter of Monday’s 3-0 preseason win over Oakland. Witten caught a pass from Tony Romo for a loss of two yards and was belted by Raiders linebacker Rolando McClain. Witten immediately popped up and went to the sideline, and wasn’t in the game for the next play, suggesting his night was over.

However, he returned to the game with the first-team offense for the next series and even caught an 8-yard pass. It was the final play of the game for both Witten and the majority of the Cowboys starters.

After the game, Witten said he was "fine" but owner Jerry Jones said he held his breath when he saw his tight end take that hit.

The Cowboys are now with serious depth issues at tight end. Not only is Witten now out for a few weeks, but backup John Phillips has been out with an ankle injury and could start to practice this week. After that, it’s only a pair of rookies in James Hanna and Andrew Szczerba, meaning it’s likely the Cowboys will sign a tight end as early as Wednesday.

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