Investing in mutual funds for retirement is never too late. And the Zacks Mutual Fund Rank can be an excellent tool for investors looking to invest in the best funds.

The easiest, most reliable way to judge a mutual fund's quality over time is by analyzing its performance, diversification, and fees. The Zacks Mutual Fund Rank, which covers over 19,000 mutual funds, has helped us identify three outstanding options that are perfect for any long-term investors' portfolios that is retirement-focused.

Let's learn about some of Zacks' highest ranked mutual funds with low fees you may want to consider.

John Hancock Disciplined Value R2 (JDVPX Quick QuoteJDVPX - Free Report) : 1.15% expense ratio and 0.61% management fee. JDVPX is a part of the Large Cap Value category, and invests in equities with a market capitalization of $10 billion or more, but whose share prices do not reflect their intrinsic value. JDVPX has achieved five-year annual returns of an astounding 12.07%.

MM Select Equity Asset I (MSEJX Quick QuoteMSEJX - Free Report) is a stand out amongst its peers. MSEJX is a Global - Equity mutual fund investing in bigger markets like the U.S., Europe, and Japan; these kinds of funds aren't limited by geography. With five-year annualized performance of 16.27%, expense ratio of 0.28% and management fee of 0.18%, this diversified fund is an attractive buy with a strong history of performance.

Neuberger Berman Genesis Investor (NBGNX Quick QuoteNBGNX - Free Report) is an attractive large-cap allocation. NBGNX is a Small Cap Value mutual fund option, which typically invest in companies with market caps under $2 billion. NBGNX has an expense ratio of 0.99%, management fee of 0.92%, and annual returns of 10.35% over the past five years.

These examples highlight the fact that there are some astonishingly good mutual funds out there. If your advisor has you in the good ones, bravo! If not, you may need to have a talk.