The 6-foot-5 Harris previously spent two seasons with the Cleveland Cavaliers.
Harris will earn $52,017 with the Lakers. After his contract expires, the team can re-sign him for one additional 10-day contract, ink him for the rest of the season or let him go as a free agent.
With the addition of Harris, the Lakers' roster is full with 15 players, although not all will be available on Friday when the team visits the Boston Celtics.
In addition to the five players out with injury (Kobe Bryant, Steve Nash, Steve Blake, Jordan Farmar and Xavier Henry), Nick Young will sit out Friday with a one-game suspension for throwing a punch Wednesday in a loss to the Phoenix Suns.
D-Fenders player development coach Luke Walton, a former Lakers forward, spoke highly of Harris in a recent phone interview with The Times.
"With [Lakers Coach Mike] D'Antoni's system, if you're a scorer, there's a lot of space available on the court out there," said Walton. "Manny is doing a great job taking advantage of that."
On Monday, Harris was named NBA D-League performer of the week for the second straight week.
With the D-Fenders, Harris has shot 48.5% from the field and 87.2% from the free-throw line. His three-point range appears limited, judging by his 25.7% shooting percentage from behind the arc.
Harris is also averaging 2.08 steals a game along with 3.7 assists and 3.08 turnovers.
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