Hard to believe there was a time when Clay Buchholz saw his name mentioned in trade talks almost every winter. From Jarrod Saltalamacchia to Roy Halladay, it seemed every available major leaguer was coming to town in exchange for the young righty.

Red Sox fans should be thankful that never happened. Extremely thankful.

In this 2010 baseball season where reserves have become regulars, a season in which the team’s Opening Day starter has a .500 record and a 6.67 ERA, Buchholz has been the cornerstone of whatever playoff hopes the team carries into September.

After Sunday’s rain-drenched win at Fenway Park, Buchholz held the lowest ERA in the American League at 2.26, the latest in a season a Boston pitcher has led the league in ERA since Pedro Martinez in 2003. Buchholz already had the league’s lowest ERA when he first took the mound on Sunday, but managed to lower it with six shutout innings. He has now gone 23 1/3 innings without giving up an earned run, managing to beat the Blue Jays – and two rain delays – to keep that streak intact.

The rain was just another reminder that nothing has come easy for Buchholz this season. At mid-season, he was under serious consideration to be the starting pitcher for the American League at the All-Star Game. Instead, he spent his time in Anaheim on the sidelines, on the disabled list with a strained hamstring. In his first start back, he was pounded for five runs in just four innings. We wondered if the DL stood for derail, worried that a remarkable first half would be nothing more than a footnote.

Buchholz is 5-0 since that loss, and is firmly in the midst of the Cy Young argument. With 15 wins, he could become just the third Red Sox pitcher in the last eight years to win 20 games in a season.

On Sunday, he dazzled the Blue Jays with an assortment of blazing fastballs, nasty change-ups, and the occasional curveball. He has always featured those pitches, but now sinks and cuts his fastball to keep hitters off balance. He has the type of arsenal we dreamed about when Daisuke Matsuzaka first arrived on our shores in 2007.

Buchholz has always had great stuff. Now he’s got the maturity to go along with it. We’ve seen glimpses of what he can do, beginning with the 2007 no-hitter against Baltimore in just his second big-league start. He was essentially a late-season call-up, making a spot start for the Sox. Instead, he made history.

He became a victim of that early success the following year, finishing 2008 in the minors. He was back by midseason last year, and has never looked back. With September now just over a week away, Buchholz is the undisputed leader of the pitching staff. The Sox are still alive, hanging in there while the Yankees and Rays deal with injuries of their own. Yet time has become an enemy.

There are just 36 games remaining in the season, and if the Sox are going to make an improbable run to the postseason they’re going to do it with a roster filled with players who never expected to call Fenway Park home this season.

As we’ve said all season, they would have to do it on the basis of strong pitching. And while big-money signees like Josh Beckett and John Lackey have disappointed, Buchholz and Jon Lester have not. They are the two young men who will shoulder the pitching load for this team in the future. We knew Lester was an ace, we were waiting to see just how high Buchholz could go.

The wait is over. Buchholz is one of the best in the game. No matter what becomes of his team this season, 2010 will go down as an unqualified success for him.

Tom Caron is the studio host for Red Sox broadcasts on the New England Sports Network. His column appears in the Press Herald on Tuesdays.