SANTA CLARA -- Alex Smith's upstanding yet somewhat unfulfilling 49ers career will end with a trade to the Kansas City Chiefs, multiple NFL sources told the Bay Area News Group on Wednesday.

The deal, which can't be ratified until March 12, has the 49ers poised to collect a second-round draft pick this year and a conditional third-round choice in 2014. That later pick could climb to a second-round selection based on Smith's playing time and Kansas City's success, a source stated.

With the Chiefs' second-round pick (No. 34 overall), the 49ers stand to own 15 picks in April's draft, including 11 already in hand plus another three compensatory picks that are expected to be announced later this month.

Left tackle Joe Staley, one of Smith's closest friends, tweeted: "Best of luck to Alex in KC. Amazing teammate, friend, and person. I know he will do great things there."

Neither the 49ers nor Chiefs would confirm the trade, which can't be completed until the NFL's new fiscal year begins. Smith was unavailable for comment.

Kansas City is a familiar landing spot for former 49ers quarterbacks, including most notably Joe Montana's trade there in 1993. Other ex-49ers who went on to start for Kansas City were Steve DeBerg, Steve Bono and Elvis Grbac.

Montana was a 36-year-old, four-time Super Bowl winner when the 49ers packaged him, safety David Whitmore and a 1994 third-round pick to the Chiefs for the 18th overall pick in 1993.

Smith, 28, was drafted first overall in 2005 out of Utah. His tenure seemed complete ever since Colin Kaepernick burst onto the scene in November and helped lead the 49ers to the Super Bowl.

Trent Dilfer, a former 49ers quarterback and one of Smith's confidants, spoke highly of the prescribed trade and expects the 49ers to produce a Super Bowl-filled dynasty this decade.

"This trade is stealing for the Niners," Dilfer, now an ESPN analyst, said on "NFL Live." "I can not believe they got a second and a conditional out of this. ... They are set up to not just be successful next year and the year after that, but five, six, seven years."

The Chiefs, under new leadership with coach Andy Reid and general manager John Dorsey, hold the first overall draft pick on April 25, based on last season's 2-14 record that tied as the league's worst with the Jacksonville Jaguars.

Fox Sports' Jay Glazer first reported Wednesday that the Chiefs would be Smith's destination. A deal was deemed "effectively complete" Sunday according to a report then by CBS Sports' Jason LaConfora.

In the days leading up to the Super Bowl, Smith denied a report that he would request his release, but he didn't mask his desire to start again. "I want to play football. I'm not hiding that fact," Smith said Jan. 30. "I love this team. I love being a part of it and of what's going on, but I want to play football."

Smith hasn't demanded who should be his next suitor, according to a source, but he did provide the 49ers a list of his preferred teams, and that Kansas City was near the top or at the top of that list. General manager Trent Baalke revealed last week that he recently had dinner with Smith and his wife, Elizabeth, to discuss their options.

Former Kansas City Chiefs general manager Scott Pioli said he wasn't surprised at Smith's price tag on the trade market. "But the one thing I've heard in talking to some good sources is that this thing hasn't been completely finalized yet," Pioli told SiriusXM NFL Radio. "I think they're still working through some of the absolute details on what the compensation is."

Pioli suggested that the Chiefs may look to acquire a lower-round pick with Smith before the deal is completed in two weeks. "What's been a new trend in the NFL is people generally kick picks back," Pioli added. "Even if they're going to give up a higher pick, they want to get something later in the draft so they at least have a volume of picks to have more opportunities."

Smith's career was hindered early by poor supporting casts, coaching changes and a 2007 shoulder injury. He emerged as one of the league's most efficient passers the past two seasons under coach Jim Harbaugh.

Smith has compiled a 38-36-1 regular-season record as a 49ers starter, including a 19-5-1 mark since 2011 before sustaining a Nov. 12 concussion that cost him his starting job.

Safety Donte Whitner tweeted: "Good luck to Mr. Alex Smith. I know you'll do great under Andy Reid in KC. The ultimate pro!"

Scott Tolzien is poised to serve as Kaepernick's backup with the 49ers. Another possible option is brining back Josh Johnson, a pending free agent who was cut after last season's exhibition season with the 49ers.

Dating back to halftime of an Oct. 18 win over Seattle, Smith completed 36 of his final 39 passes for 391 yards with five touchdowns and one interception. He did not play in any of the 49ers' three playoff games.

In his last full outing, Smith completed 18 of 19 passes in a 24-3 win at Arizona on Oct. 29, earning him a first-career NFC Offensive Player of the Week award. His career passing stats: 1,290-of-2,177 (59.3 percent), 14,280 yards, 81 touchdowns, 63 interceptions, 196 sacks.

Once Harbaugh stuck with Kaepernick over a medically cleared Smith for a Nov. 25 start at New Orleans, Smith's backup status was sealed. "It sucks. I don't know what else to say," Smith said on Nov. 29. —I feel the only thing I did to lose my job was get a concussion."

Smith's benching did not become a divisive force inside the locker room as the 49ers went on to win their second straight NFC West title and reach their second straight NFC championhip game.

Despite leading the 49ers to a playoff-opening win over the New Orleans Saints in the 2011 season, Smith's future was cast in doubt last year as he became a free agent and the 49ers "evaluated" Peyton Manning. Once Manning opted to sign with the Denver Broncos, the 49ers re-signed Smith to a three-year, $24 million contract that allowed them to escape the deal this offseason. Smith would be guaranteed $8.5 million for this season only if he's on the 49ers' roster April 1.

Matt Cassel has been the Chiefs' starting quarterback most of the past four seasons, since they acquired him in a 2009 trade with the New England Patriots.Casselis expected to be released.

The Chiefs had six players make last season's Pro Bowl, with 1,500-yard rusher Jamaal Charles their offense's lone representative. After winning the AFC West in 2010, the Chiefs finished in last place each of the past two seasons.

Reid, the Chiefs' third coach in three seasons, was interested in Smith last offseason as Reid prepared for his 14th and final season with the Eagles, according to previous comments from Dilfer.

Perhaps furthering the Chiefs' interest in Smith is that Dorsey is on record as saying this draft class lacks a quarterback worthy of the top pick. None of the past 10 quarterbacks drafted by the Chiefs produced a win as a starter, according to ESPN.Montanadelivered the Chiefs' last playoff win, when he led them to the AFC Championship game upon his arrival in the 1993 season.

Smith is 0-2 lifetime against the Chiefs, losing both times at Arrowhead Stadium. The 49ers lost 41-0 there in his 11th career start on Oct. 1, 2006; incidentally, Kaepernick's next start will be his 11th.

What are the chances Smith succeeds inKansas City? One Internet wagering site projected Smith's 2013 over-under lines with the Chiefs: 3,000 passing yards, 18 ½ touchdowns and 10 ½ interceptions.

The 49ers' draft-pick war chest would include five of the first 93 selections: No. 31 overall, No. 34 (from the Chiefs), No. 61 (original second-round pick), No. 74 (third-round choice, acquired from the Carolina Panthers last draft) and No. 93 (original third-round pick). They also own two picks in the fifth, sixth and seventh rounds prior to the upcoming compensatory choices they'll be awarded, having accrued those multiple picks via trades with the Indianapolis Colts (fifth round), Miami Dolphins (sixth round) and Cincinnati Bengals (seventh round).

A Facebook page impersonating Smith carried a phony, farewell message that the 49ers stated was not from the quarterback. But that post generated thousands of "likes" and comments, including this one: "Two words: BEAT OAKLAND."