Who will have Cubs' next retired number?

CHICAGO -- There are five flags that fly on the poles at Wrigley Field to honor numbers no player can wear now for the Cubs. It is an exclusive group that features players who each carved out lasting legacies with the franchise.

10: Ron Santo
14: Ernie Banks
23: Ryne Sandberg
26: Billy Williams
31: Fergie Jenkins and Greg Maddux
42: Jackie Robinson (MLB-wide)

There are no firmly established criteria for a player reaching retired-number consideration for the Cubs, though all six are in the Hall of Fame. That said, Santo and Maddux had their numbers retired by Chicago prior to enshrinement, so induction is not a requirement ahead of time. The club considers years with the team, impact, awards and legacy, but it does so without any strict stipulations.

• Cubs' retired numbers

With that in mind, who might be next to have their number retired by the Cubs? Here are six possibilities.

ACTIVE CANDIDATES
17: Kris Bryant
Bryant has a long way to go in his career, but he's certainly on a Hall of Fame trajectory through his first five seasons. He already has a National League Rookie of the Year Award (2015), an NL Most Valuable Player Award ('16) and a World Series ring for a franchise that went 108 years without a title before the '16 triumph. Bryant's 138 homers are the most by a Cub in his first five seasons, passing Banks' 136.

Retiring No. 17 would also be appealing for Chicago because it was worn by Cubs great Mark Grace. It could be similar to how retiring No. 31 honored both Jenkins and Maddux. Over 13 seasons, Grace won four Gold Glove Awards for the Cubs, and he led the Major Leagues in hits (1,754) and doubles (364) in the 1990s. He is second on the Cubs' all-time list for doubles (456) and fifth in hits (2,201).

34: Jon Lester
Lester's candidacy would be based more on impact than raw numbers. The lefty has arguably been the best free-agent signing in franchise history, arriving in 2015 for the start of the Cubs' turnaround and serving as the rotation's figurehead during one of the greatest eras in club history. He was second in NL Cy Young Award voting in '16, when he was also the NLCS MVP along with Javier Báez, and then he won his third career World Series ring. It's also worth noting that No. 34 was also worn by Cubs great Kerry Wood.

There are two things working against Lester's case, however. First, he could wind up being a borderline Hall of Fame candidate. Second, if Lester is worthy of having his number honored, some fans might wonder why Jake Arrieta isn't also being considered. Lester has gone 74-41 with a 3.54 ERA in five seasons. Arrieta went 68-31 with a 2.73 ERA and the 2016 NL Cy Young Award in parts of five years.

44: Anthony Rizzo
Over eight seasons with the Cubs, Rizzo has been carving out the kind of legacy that will have his name mentioned alongside the franchise's all-time greats for generations. He came to the Cubs in 2012 via trade, giving the club a critical core piece as the franchise constructed its World Series-winning roster. Fittingly, Rizzo caught the final out of that Fall Classic.

Rizzo might ultimately find himself in Grace's category -- an all-time franchise icon who does not rise to Hall of Fame standards. Time will tell. For now, he has three NL Gold Glove Awards and three All-Star appearances, and he serves as a symbol of the Cubs' transformation in the past decade. Rizzo has also made an enormous impact off the field with his foundation's work in Chicago and other communities.

HISTORIC CANDIDATES
8: Andre Dawson
Dawson was inducted in the Hall of Fame in 2010, and he is understandably wearing an Expos cap on his plaque. The outfielder spent 11 years with Montreal, compared to six with the Cubs. In that time in Chicago, however, Dawson was named to five of his eight career All-Star teams, picked up two of his eight NL Gold Glove Awards and won the NL MVP Award in 1987. The length of Dawson's time with the Cubs is what works against him.

46: Lee Smith
Of the six names on this list, Smith is the most likely to have his number retired first. The legendary closer was inducted into the Hall of Fame in 2019 and went into Cooperstown as a Cub. Smith notched a club-record 180 saves with Chicago and was MLB's all-time saves king with 478 before Mariano Rivera (652) and Trevor Hoffman (601) surpassed his record. In eight years with Chicago, Smith had a 2.92 ERA in 458 games. It's worth noting that Pedro Strop (also one of the best relievers in Cubs history) wore No. 46.

21: Sammy Sosa
While Sosa's relationship with the Cubs has been strained in recent years, and he has struggled to gain momentum in Hall of Fame voting -- he's hovered between 6.6 percent and 13.9 percent over the past eight cycles -- this list would be incomplete without him. Sosa electrified MLB with his pursuit of the single-season home run record in 1998 and launched a club-record 545 blasts (out of 609 total) with the Cubs. He topped 60 homers three times, won an NL MVP ('98) and made seven All-Star teams.