The knuckleball is one of the most unpredictable oddities in baseball.

When it's working, it's unhittable. When it's not, things can get ugly awfully fast.

Tim Wakefield has certainly experienced both sides of the knuckler in his nine-year career with the Red Sox. But for the most part this season, Wakefield has been the picture of stability in the middle of the starting rotation.

The Sox, who will give the ball to Wakefield tonight for Game 2 of a pivotal three-game set against the Oakland Athletics at Fenway Park, are 5-0 in the last five games he has started. Last night's 3-2 loss in the series-opener makes tonight's game all the more important for Wakefield and the Sox.

In his last 10 starts, the knuckleballer has failed to make it through the sixth inning only once, when he pitched 5 innings against the Orioles on Aug. 3, a game which the Sox won and Wakefield earned the decision.

Wakefield's 140 strikeouts had him tied for fifth in the American League entering last night, trailing only former and current Cy Young candidates Pedro Martinez, Mike Mussina, Roger Clemens and Roy Halladay. Opponents are batting .240 against Wakefield, seventh-best among AL hurlers, and right-handers are hitting a meager .214 against.

Though the knuckleball can have a mind of its own, the Sox have every reason to be confident in Wakefield and the right-hander has every right to be eager for tonight's start.

``Absolutely,'' Wakefield said. ``It's something you've worked for in the offseason to get to this point. You take it as a challenge and I'm looking forward to my starts against Oakland and Seattle and New York.''

Wakefield (9-5, 4.10 ERA) will pitch opposite A's left-hander Ted Lilly (6-9, 4.71). In his last start, Wakefield didn't get a decision, but he allowed only two runs on five hits over six innings and kept the Sox in a game they eventually won in extra innings in Oakland.

As the Sox opened a 12-game homestand, Wakefield saw the lengthy Fenway stretch as an important time to cash in on their dominance at home (39-19) and put some space between themselves and the Athletics. The Sox need a win tonight, however, just to pull back even with Oakland in the AL wild card race.

``We'd like to do that and that's our goal, to get some breathing room, but you can't play a whole series in a day,'' said Wakefield. ``It would definitely be to our advantage to try and win these games. It's just a matter of going out there and not taking things for granted and try and really push hard, because the games this time of year are so important.''