Surprise, Ariz. ? Royals third baseman Alex Gordon is expected to be sidelined for three to four weeks due to a broken right thumb.

Manager Trey Hillman said Sunday that Gordon probably will miss Kansas City’s April 5 opener against Detroit, but the No. 2 overall pick in the 2005 draft is optimistic about his chances of playing.

“That’s the way I’m taking it,” Gordon said. “Hopefully, I’ll be able to get into games at the end of spring training. I really haven’t found out exactly the timetable and maybe if I can come back earlier or not. We’re just going to see how the first couple of days progress and go from there.”

Gordon was injured when he slid headfirst into second base on an attempted steal in the second inning of the Royals’ 2-1 victory over the Texas Rangers on Saturday.

“I kind of knew something was up, but I didn’t want to tell myself something was wrong,” Gordon said. “I tried to play through it.”

Gordon remained in for five innings, but postgame X-rays detected the fracture.

“It was black and blue, and something was popping out, so the doctors looked at it and said we should get an X-ray,” Gordon said after Sunday’s spring game against San Francisco was rained out.

Gordon, who throws right and bats left, will not be allowed to throw or swing a bat while he is out.

“I can take ground balls, conditioning, stretch and do other things with the team,” he said.

Gordon had hip surgery last April and played in only 49 games, hitting .232 with six homers and 22 RBIs.

Hillman said Alberto Callaspo and Josh Fields would get most of the reps at third base with Gordon out. Callaspo hit .300 with 11 homers last year while mostly playing third base. Fields, who hit 23 homers as a rookie in 2007, was acquired in an offseason trade with the Chicago White Sox.

Hillman also said shortstop Jeff Bianchi, one of the Royals’ top prospects, will have Tommy John surgery on his right elbow.