Diamondbacks 1B Jackson day-to-day

May 8, 2008 - 4:54 PM PHOENIX (Ticker) -- Arizona Diamondbacks first baseman Connor Jackson is listed as day-to-day after being involved in a scary collision in Wednesday's game against the Philadelphia Phillies.

In the eighth inning of the Phillies' 5-4 victory, Philadelphia's Shane Victorino took off for first base after he struck out and the ball got past Arizona catcher Chris Snyder.

Both players arrived at the bag simultaneously, resulting in a violent collision as Victorino's helmet caught Jackson on the right side of his face under his eye.

Jackson was forced to leave the game but never lost consciousness, and the Diamondbacks do not yet know if he suffered a concussion.

"I'm all right," Jackson said after the game. "Just a little headache. It was kind of a fluky play, you could say. I was a little bit nauseous."

Wednesday was Jackson's 26th birthday. One inning earlier, he delivered an RBI double that had given the Diamondbacks a 4-3 lead. The Phillies scored two runs in the eighth.

Snyder blamed himself for the collision at first base.

"We never should have been in that situation," he said. "I should have caught the ball."

Jackson has enjoyed a breakout season so far for the first-place Diamondbacks, batting .339 with five home runs and a team-leading 28 RBI.