Manningham was not part of future plan

One of the reasons the San Francisco 49ers were investigating free agent receivers in recent days is that one of their last acquisitions at the position didn’t work out.

Now, Mario Manningham will try to revive his career with his original team. ESPN’s Adam Schefter reported Manningham signed a one-year deal with the Giants. After being a Super Bowl hero for the Giants, Manningham signed a two-year deal with the 49ers in 2012.

Manningham was fairly effective in his first season with 42 catches, second most on the team. But he suffered a major knee injury late in the season. He debuted in November during the 2013 season, but never was healthy and fell out of the playing rotation. He was shelved again late in the season.

It was evident when Manningham was hurt again the 49ers would move on. Tuesday’s development was neither surprising nor disruptive to the 49ers’ plan for 2014.

In other 49ers news:

As part of his deal with Buffalo, former 49ers running back running back Anthony Dixon signed a three-year deal with $750,000 in guaranteed money.

The 49ers should be on pace to get a compensatory draft pick next year based on the fact more free agents have departed than signed with the 49ers. The formula, which is complex, won’t be determined until next year. The 49ers should get a third- or fourth-round comp pick for this year’s draft as soon as next week at the owners' meetings.

According to ESPN Stats & Information, the 49ers have $3.8 million in salary-cap space, the fifth least in NFL. They will get more than $6 million in cap space in June per the Carlos Rogers cut.

The additional money will mostly likely be used to sign draft picks.