For months, Mark McGwire said it would not, could not happen again, at least not like last season, when he and Sammy Sosa captivated a nation with their home runs, grace and goodwill. This afternoon, he showed he might be wrong.

After Sosa homered twice on Friday and twice on Saturday to take the major league lead, McGwire responded with a pair of home runs of his own this afternoon in the first game of the St. Louis Cardinals' doubleheader with the New York Mets.

McGwire's home runs were his 49th and 50th of the season. Both came in the first game of the doubleheader and left him one behind the Chicago Cubs' Sosa, who hit his 50th and 51st on Saturday but was held without one today in a home game against the Colorado Rockies.

McGwire left New York's Shea Stadium with the same number of home runs he had at this point a year ago -- 50 home runs in 125 games on his way to a record-setting 70. Sosa is ahead of last year's pace, hitting his 51st home run nine games earlier than last season, when he finished with 66.

Last season's duel between the two sluggers was viewed as an historic happening, the likes of which baseball would never see again. It had been 37 years since Roger Maris had hit 61 home runs, and no one had come close until McGwire tied, then passed him on Sept. 8. Sosa, too, equaled and surpassed Maris, just five days later. That baseball fans could be treated to another such spectacle seemed inconceivable.

"After the year I had last year, a lot of people thought I wasn't going to do it again," Sosa said Saturday after moving ahead in the chase. ". . . Can I hit 70? I don't know."

Thus far, the home run race has not drawn the media attention it did last year, and even McGwire himself does not feel the charge that came from venturing into uncharted baseball territory.

"This year is different," he said. "There's not a catch yet as far as the excitement goes. For me, I'm chasing myself. I'm not as excited about that. Last year we were chasing history, chasing 61. This is much lighter. All we can do is play and whatever happens, happens."

Both McGwire's Cardinals and Sosa's Cubs are far out of playoff contention, so the home run race -- McGwire calls it "Home Run Derby II" -- will be what brings fans to their ballparks in the closing weeks of otherwise disappointing seasons.

McGwire's and Sosa's home runs have made them the most recognizable people in professional sports. While McGwire is clearly bothered by his lack of privacy, he has performed in the spotlight with what Commissioner of Baseball Bud Selig calls "a grace and dignity I can't even begin to put into words." And he has stopped using the over-the-counter dietary supplement androstenedione, a substance banned in some other sports, because of concerns that young athletes were emulating him.

This afternoon, McGwire signed autographs for two hours before the doubleheader, then held a chatty news conference afterward.

"People always want a piece of me," he said. "I've always known that, but after last year, I never realized there were so many things they could want one person to do -- whatever it may be. Probably the hardest thing is learning how to say no. I have the right to say no. I can't please everybody. I try to be myself and do what I can. It's just made me a stronger person."

Sosa, by contrast, relishes the attention heaped upon him and has said he is enjoying his accomplishments of this season every bit as much the second time around.

Sosa's popularity was affirmed this month when the Cubs visited St. Louis for a three-game series. After going wild for McGwire during batting practice, Cardinals fans gave Sosa thundering ovations as well.

Still, it is McGwire's home runs that most often leave onlookers breathless and in awe. McGwire hits home runs, and then he hits some home runs that players and fans will tell their grandchildren about. One of those occurred in the first inning of today's opening game when he hammered a fastball from Mets rookie Octavio Dotel off the gigantic scoreboard in right-center field.

The ball knocked out the light bulb illuminating the No. 16 that represented teammate Ray Lankford's jersey number. The Mets measured the home run at 502 feet -- McGwire's longest of the season.

"I can only do what I'm capable of doing," he said. "It's not easy. I know people say, `What's wrong? You didn't hit a home run today.' I hear that when I walk down the street. I wish it was easy. It's not."

But once again this season, McGwire and Sosa have made one of the most difficult feats in baseball -- hitting a pitch over the fence -- seem almost simple.

"Seventy is like ridiculous -- it really is," McGwire said. "I think 60 will be gotten again. Seventy is an extra 10. It is unfathomable when you think that I had to hit five in the last three days to get there. I don't know how you can ever dream about it."