The merger between the NFL and AFL was complete, with the leagues now playing each other in the regular season for the first time. This was the last step in a four-year process that began in January 1967 with the champions from both leagues playing in Super Bowl I.
To finish the merger, the Browns, along with the Pittsburgh Steelers and Baltimore Colts, agreed to move in 1970 from the NFL to the old AFL, renamed the AFC, to balance the leagues, now called conferences (NFC and AFC), at 13 clubs each. The merger had hit a stalemate when none of the NFL teams initially wanted to jump to what many of the old-line NFL people felt was an inferior league overall.
Concerning just the Browns themselves, there was the situation involving Blanton Collier. Although no one except maybe the man himself knew it at the start of the season, this was going to be the last year for the venerable head coach. Collier, who had been on the job since 1963 and had guided the Browns to the NFL championship a year later, would announce his retirement shortly before the 1970 season ended.
Realizing quarterback Bill Nelsen's aching knees were on borrowed time, the Browns had made a blockbuster trade with the Miami Dolphins on the eve of the 1970 NFL Draft to get the rights to select the man they felt would be their passer of the future, Mike Phipps. But it came at a steep price, for they had to give up Pro Football Hall of Fame wide receiver Paul Warfield in the process. That loss, coupled with Nelsen's physical condition and the unfamiliarity with the personnel on the former AFL clubs they were playing for the first time, took the starch out of what had been a good offense going all the way back to 1963. The result was the Browns scored 65 less points than they had the year before, and 108 less than two seasons before.
Along with that, the defense, though it gave up 35 fewer points than it had in 1969, just couldn't make up the difference, led to the Browns finishing 7–7, only the second non-winning mark in club history. In spite of that, the season started well for the Browns, as they opened 3–1 and then were 4–2.
The Browns beat Joe Namath and the New York Jets 31–21 at Cleveland Stadium in the opener in the first Monday Night Football game in history, and, three games later, edged Cincinnati 30–27 in Bengals head coach Paul Brown's first official visit to Cleveland since being fired by the Browns eight years before.