Update: The deal is in the process of being finalized, but it is not official yet.

The Red Sox are in serious talks and moving closer to a deal to acquire closer Joel Hanrahan from the Pirates, according to CBSSports.com's Jon Heyman. Gordon Edes of ESPN initially reported that the two sides were close to a deal.

Edes reported the deal was close, though a source told him there is "still work to be done." It’s unclear what the Red Sox would send to Pittsburgh in the deal, but the Pirates were reportedly looking for a "significant return" for Hanrahan, 31.

It was speculated earlier in the offseason that Jose Iglesias could be involved in a deal for Hanrahan, but Heyman has heard he is not a part of the trade talks. Outfielder Jerry Sands could be involved, according to Heyman. The 25-year-old Sands hit .296/.375/.524 in Triple-A last season. 

Whether Boston gives up a significant piece depends on how much it values saves. Hanrahan collected 76 saves over the past two seasons but saw his numbers drop this year. He still managed to strike out more than a batter per inning, but his control was a big problem. His walk rate jumped to 14.2 percent, his highest since 2007.

While he still had a strong 2.72 ERA, Hanrahan's 4.45 FIP indicates he could be in for a bit of regression next season. Hanrahan also struggled giving up home runs, which would likely to remain an issue in Boston.

For more up-to-the-minute news and analysis on the latest rumors from bloggers Chris Cwik, Jack Moore and R.J. White, follow @MLBRumorsCBS.