Masahiro Tanaka is expected to announce his highly-anticipated decision this week and reports say five teams are in the mix for the free agent Japanese pitcher.

The New York Yankees and the Los Angeles Dodgers were previously identified as the finalists for Tanaka, but recent reports suggest that the Chicago White Sox, Chicago Cubs, and the Arizona Diamondbacks also submitted strong bids.

Fox Sports, citing a Japanese newspaper, reported that the Diamondbacks officially put themselves in the running as they issued a six-year, $106-million offer to the 25-year-old pitcher.

The reported offer proved Arizona's strong interest in Tanaka; it could be the largest contract in franchise history if the right hander accepts the Diamondbacks' offer. It would eclipse the five-year, $60-million extension signed by Miguel Montero in 2012.

The Dodgers have also put an offer on the table, but financial terms were not disclosed. It's no secret that signing Tanaka is one of the club's top priorities this offseason.

The Dodgers and Clayton Kershaw recently agreed to a lucrative seven-year deal worth $215 million. General manager Ned Colletti clarified that giving Kershaw the biggest salary for a pitcher in MLB history won't affect their bid to sign Tanaka.

"We're still, first and foremost, concerned with the quality of the team we can put together, and adding it up comes second," Colletti told ESPN. "This is a long-term strategy of ours. After five or six or seven years, it will make a lot more sense than it does to people looking at today's snapshot."

Meanwhile, the Boston Globe identified the Cubs as one of the strongest contenders based on the amount of contracts that they can offer. Reports suggested that the bidding could go as high as $120 million for six years.

The Yankees, who were considered as front-runners since Tanaka's name began floating around the free agency market, are still looking to stay under the $189 million luxury tax threshold, but their plan won't stop them from enticing Tanaka to play in New York next season.

"The luxury-tax goal has not at all hindered their pursuit of Tanaka, Steinbrenner insisted, and an industry source said the Yankees have made a "very aggressive" offer to the 25-year-old. They would rather win on Tanaka and lose on their luxury-tax goal," the New York Post reported.

Tanaka, who went 24-0 with a 1.27 ERA with the Rakuten Golden Eagles of the Japanese League last season, is expected to make his decision ahead of the Jan. 24 deadline.