After three straight years in the NBA lottery, things appear to be looking up for the Cleveland Cavaliers.  Does the addition of center Andrew Bynum to Cleveland's young, talented cast now make the Cavs an instant playoff contender? 

The Cavaliers took a gamble on Wednesday and signed the injury-plagued Bynum to a two-year deal.  The contract is only partially guaranteed, but could pay as much as $24.5 million, according to USA Today.  The 2013-14 season is guaranteed for $6 million, but the deal could reach $12 million with incentives; the second year is a team option worth $12.5 million.

Cleveland's hopes and dreams rely on the knees of Bynum.

Bynum hasn't played in a game since May 21, 2012.  He missed his entire first year with the Philadelphia 76ers, who made a blockbuster trade for the center last summer.  Although only 25, Bynum has a lengthy medical history of knee surgeries and bone bruises.  One report in February indicated an MRI revealed Bynum's knees to be degenerative.

While signing Bynum was a risk, partly mitigated by the non-guaranteed contract, there's huge upside if he remains healthy.  He is one of the top centers in the league.  Before missing his inaugural season with the Sixers, Bynum averaged 18.7 points, 11.8 rebounds and 1.9 blocks during the 2011-12 season with the Lakers.

A healthy Bynum can make Cleveland a playoff team.  The team is young and filled with high-upside draft picks.  Kyrie Irving, the 2011 No. 1 pick, is quickly becoming one of the league's top guards (22.5 points, 5.9 assists last season).

Tristan Thompson, the 2011 No. 4 pick, made a big leap last season and nearly averaged a double-double, with 11.7 points and 9.4 rebounds per game.  

2012 No. 4 pick Dion Waiters showed promise as a 2-guard, averaging 14.7 points in his rookie campaign, and this year's No. 1 pick, Anthony Bennett, gives the Cavs a promising 6-foot-8 rookie that can score and rebound.

Bynum can round out a talented team that has a solid bench, headlined by Jarrett Jack and Alonzo Gee.  Cleveland needs either Bynum or Anderson Varejao, who led the NBA in rebounds last year prior to his injury, to be healthy.  If either of the centers can stay healthy, and if coach Mike Brown's system can improve the team's league-worst defense, the Cavs will be playoff team capable of making a deep run.

*UPDATE: Irving and Thompson were drafted in 2011.