Considering the Phillies had fewer hits than any team in the majors this year, starting pitching isn't the highest-priority item on their offseason shopping list.

Yet they are courting the top pitcher on the free-agent market.

While the baseball world waits on Bryce Harper and Manny Machado, Patrick Corbin visited Citizens Bank Park on Monday for a recruiting session with Phillies officials, a source and a tweeted photo of the left-field scoreboard confirmed. It was unclear whether the 29-year-old lefthander has received an offer or is close to choosing a team, but his presence signaled that there is mutual interest in him joining a Phillies rotation that has been decidedly right-handed since the end of the 2016 season.

Corbin, who could command a contract that is worth in excess of $100 million, has been solid but hardly elite for most of his six-year major-league career. From 2012 through 2017, he posted a 4.12 ERA, 1.348 walks/hits per inning pitched, 3.96 fielding independent pitching (FIP) and 7.9 strikeouts per nine innings. He missed the 2014 season after undergoing Tommy John elbow surgery.

But Corbin's value is at its peak thanks to a well-time career year in 2018. In 33 starts for the Arizona Diamondbacks, he posted a 3.15 ERA, 1.050 WHIP and 11.1 strikeouts/nine innings, and finished fifth in the Cy Young Award voting. He also excelled in the metric that Phillies manager Gabe Kapler values more highly than almost all others, sporting a 2.47 FIP that was second in the league behind only New York Mets ace Jacob deGrom, the nearly unanimous Cy Young winner.

The question now, as Corbin seeks a deal that could rival Yu Darvish's six-year, $126 million contract with the Chicago Cubs last winter, is whether 2018 represents the start of his peak or a one-year flash.

Several scouts who watched Corbin last season attributed his breakthrough to the addition of a slow curveball that augmented his wipeout slider and generated swings and misses 13.4 percent of the time, the second-highest rate among his five pitches.

"He uses it so well, too," one National League scout said of the new pitch. "In fastball counts, early in counts, et cetera, without overexposing it to the point where hitters look for it."

For most of the season, starting pitching was the Phillies' strength, so much so that general manager Matt Klentak was steadfast in his refusal to acquire pitching before the trade deadline. But the rotation, save ace Aaron Nola but including veteran righthander Jake Arrieta, faltered badly in August and September, exposing a weakness that the club underestimated earlier in the season.

Specifically, the Phillies are trying to add a lefthander to the rotation who would represent an upgrade over one of the young righties: Nick Pivetta, Vince Velasquez, Zach Eflin or Jerad Eickhoff. Over the past two years, they have gotten only three starts from a lefty — and all by 22-year-old Ranger Suarez, who began last season in double A.

"In a perfect world, we would like to have a balanced rotation," Klentak said at the general managers' meetings earlier this month. "Now, what we're not going to do is swap out a good righty for a less-good lefty. We're not going to do it just to create balance."

Corbin checks more boxes than simply throwing with the desired hand, of course. And the Phillies will have competition, particularly from the New York Yankees, Corbin's favorite team growing up in upstate New York. The Yankees have been linked to him, although their pursuit might have waned after they traded for lefty James Paxton last week.

Regardless, the Phillies will have to decide how much money to wager that Corbin is a late-blooming ace and not a one-year wonder.